Writing B2 - Skills Practice: Structure And Written Expression

1. ________, one of the most famous presidents, was assassinated by John Wilkes Booth.

For Abraham Lincoln

Abraham Lincoln was

Of all the presidents

Abraham Lincoln

This sentence contains a verb was assassinated but needs a subject; presidents is the object of the preposition of and is not the subject. Answer D is the best answer because it contains the subject Abraham Lincoln. Answers A and C each contain a prepositional phrase, and answer B contains an extra verb, so these answers are incorrect.

Explanation

This sentence contains a verb was assassinated but needs a subject; presidents is the object of the preposition of and is not the subject. Answer D is the best answer because it contains the subject Abraham Lincoln. Answers A and C each contain a prepositional phrase, and answer B contains an extra verb, so these answers are incorrect.

2. John Butterfield ______ the Southern Overland Mail Company with two stagecoaches in 1858.

He set up

Setting up

Set up

The setup

This sentence contains a subject John Butterfield but needs a verb. Answer C is the best answer because it contains the verb set up. Answer A contains an extra subject, answer B contains a present participle, and answer D contains a noun, so these answers are incorrect.

Explanation

This sentence contains a subject John Butterfield but needs a verb. Answer C is the best answer because it contains the verb set up. Answer A contains an extra subject, answer B contains a present participle, and answer D contains a noun, so these answers are incorrect.

3. Elephant poaching ______ the international ban on ivory was established.

Has diminished since

It has diminished

Since diminishing

It has diminishing since

This sentence contains an incomplete main clause Elephant poaching… and a complete adverb clause the international ban on ivory was established. The main clause needs a verb to be complete, and the two clauses need to be joined with a connector. Answer A is the best answer because it contains the verb has diminished and the connector since. Answer B is missing a connector, answer C contains a present participle, and answer D contains an extra subject, so these answers are incorrect.

Explanation

This sentence contains an incomplete main clause Elephant poaching… and a complete adverb clause the international ban on ivory was established. The main clause needs a verb to be complete, and the two clauses need to be joined with a connector. Answer A is the best answer because it contains the verb has diminished and the connector since. Answer B is missing a connector, answer C contains a present participle, and answer D contains an extra subject, so these answers are incorrect.

4. ______, an author probably most famous for his tales of terror, also dabbled in some science fiction.

To Edgar Allen Poe

Edgar Allen Poe

Edgar Allen Poe was

For Edgar Allen Poe to be

This sentence contains a verb dabbled but needs a subject; the commas show that author is an appositive and is not the subject. Answer B is the best answer because it contains the subject Edgar Allen Poe. Answers A and D each contain a prepositional phrase, and answer C contains an extra verb, so these answers are incorrect.

Explanation

This sentence contains a verb dabbled but needs a subject; the commas show that author is an appositive and is not the subject. Answer B is the best answer because it contains the subject Edgar Allen Poe. Answers A and D each contain a prepositional phrase, and answer C contains an extra verb, so these answers are incorrect.

5. _____ has a beautiful red coat, the red panda is called "hun-ho" or "fire fox" in China.

It

Because it

On it

As soon as

This sentence has a complete main clause the red panda is called… and an incomplete adverb clause …has… The adverb clause needs an adverb connector and a subject to be complete. Answer B is the best answer because it contains the adverb connector Because and the subject it. Answer A is missing an adverb connector, answer C contains a prepositional phrase, and answer D is missing a subject, so these answers are not correct.

Explanation

This sentence has a complete main clause the red panda is called… and an incomplete adverb clause …has… The adverb clause needs an adverb connector and a subject to be complete. Answer B is the best answer because it contains the adverb connector Because and the subject it. Answer A is missing an adverb connector, answer C contains a prepositional phrase, and answer D is missing a subject, so these answers are not correct.

6. By 1870, over 30 nations ______ their own postage stamps.

The issue

Were issuing

Issuing

They issued

This sentence contains a subject nations but needs a verb. Answer B is the best answer because it contains the verb were issuing. Answer A contains a noun, answer C contains a present participle, and answer D contains an extra subject, so these answers are incorrect.

Explanation

This sentence contains a subject nations but needs a verb. Answer B is the best answer because it contains the verb were issuing. Answer A contains a noun, answer C contains a present participle, and answer D contains an extra subject, so these answers are incorrect.

7. ______ built in 1931, the Empire State Building has actually shrunk six inches.

It was

Because it

Until it was

Since it was

This sentence has a complete main clause the Empire State Building has actually shrunk… and an incomplete adverb clause …built in 1931. The adverb clause needs an adverb time connector, a subject, and a helping verb to be complete. Answer D is the best answer because it contains the connector Since, the subject it, and the helping verb was. Answer A is missing a connector, answer B is missing a verb, and answer C contains an adverb clause connector, so these answers are incorrect.

Explanation

This sentence has a complete main clause the Empire State Building has actually shrunk… and an incomplete adverb clause …built in 1931. The adverb clause needs an adverb time connector, a subject, and a helping verb to be complete. Answer D is the best answer because it contains the connector Since, the subject it, and the helping verb was. Answer A is missing a connector, answer B is missing a verb, and answer C contains an adverb clause connector, so these answers are incorrect.

8. ______ runs parallel to the coast of California for more than 600 miles.

The San Andreas Fault is long

On the San Andreas Fault

The San Andreas Fault

Along the San Andreas Fault

This sentence contains a verb runs but needs a subject. Answer C is the best answer because it contains the subject San Andreas Fault. Answer A contains an extra verb, and answers B and D each contain a prepositional phrase, so these answers are incorrect.

Explanation

This sentence contains a verb runs but needs a subject. Answer C is the best answer because it contains the subject San Andreas Fault. Answer A contains an extra verb, and answers B and D each contain a prepositional phrase, so these answers are incorrect.

9. In a triathlon, the ______, bike, and run.

Athlete swims

Athletes swim

Swim athletically

The swimming athlete

This sentence contains a prepositional phrase In a triathlon but needs a plural subject and verb. Answer B is the best answer because it contains the subject athletes and the plural verb swim. Answer A contains a singular subject and a singular verb, answer C contains a singular verb, and answer D contains a singular subject and its adjective and is missing a verb, so these answers are incorrect.

Explanation

This sentence contains a prepositional phrase In a triathlon but needs a plural subject and verb. Answer B is the best answer because it contains the subject athletes and the plural verb swim. Answer A contains a singular subject and a singular verb, answer C contains a singular verb, and answer D contains a singular subject and its adjective and is missing a verb, so these answers are incorrect.

10. Red Ribbon Week, a national campaign to keep young people from using drugs, ______.

Annually in October

Annually in October each year

Takes place annually in October

Taking place annually in October

This sentence contains a subject Red Ribbon Week but needs a verb. Answer C is the best answer because it contains the verb takes. Answers A and B are each missing a verb, and answer D contains a present participle, so these answers are incorrect.

Explanation

This sentence contains a subject Red Ribbon Week but needs a verb. Answer C is the best answer because it contains the verb takes. Answers A and B are each missing a verb, and answer D contains a present participle, so these answers are incorrect.

11. The Statue of Liberty, completed in Paris in 1884, _______ in New York Harbor in 1886.

The unveiling

To unveil

It unveiled

Was unveiled

This sentence contains a subject Statue of Liberty but needs a verb; completed is a past participle used as an adjective and is not the verb. Answer D is the best answer because it contains the verb was unveiled. Answer A contains a noun, answer B contains an infinitive, and answer C contains an extra subject, so these answers are incorrect.

Explanation

This sentence contains a subject Statue of Liberty but needs a verb; completed is a past participle used as an adjective and is not the verb. Answer D is the best answer because it contains the verb was unveiled. Answer A contains a noun, answer B contains an infinitive, and answer C contains an extra subject, so these answers are incorrect.

12. The radiation piercing the atmosphere ______ of tanning or burning in humans.

It is the cause

Causing it

Is the cause

The cause

This sentence contains a subject radiation but needs a verb; piercing is a present participle used as an adjective and is not the verb. Answer C is the best answer because it contains the verb is. Answer A contains an extra subject, answer B contains a present participle, and answer D contains a noun, so these answers are incorrect.

Explanation

This sentence contains a subject radiation but needs a verb; piercing is a present participle used as an adjective and is not the verb. Answer C is the best answer because it contains the verb is. Answer A contains an extra subject, answer B contains a present participle, and answer D contains a noun, so these answers are incorrect.

13. ____ farmers extra hours of light by which to harvest crops before frost and winter come.

The harvest moon

Whenever the harvest moon allows

During the harvest moon

The harvest moon gives

This sentence contains a complete adverb clause before frost and winter come and an incomplete main clause …farmers extra hours of light… The main clause needs a subject and a verb to be complete. Answer D is the best answer because it contains the subject The harvest moon and the verb gives. Answer A is missing a verb, answer B contains an extra noun clause connector, and answer C contains a prepositional phrase, so these answers are incorrect.

Explanation

This sentence contains a complete adverb clause before frost and winter come and an incomplete main clause …farmers extra hours of light… The main clause needs a subject and a verb to be complete. Answer D is the best answer because it contains the subject The harvest moon and the verb gives. Answer A is missing a verb, answer B contains an extra noun clause connector, and answer C contains a prepositional phrase, so these answers are incorrect.

14. The Great Plains in the Midwest of the United States _______ a rich, fertile farming area.

Definitely making

From the beginning

The pioneers planted

Makes up

This sentence contains the singular subject Great Plains but needs a verb. Answer D is the best answer because it contains the verb makes up. Answer A contains a present participle, answer B contains a prepositional phrase, and answer C contains an extra subject and a verb that is not logical, so these answers are incorrect.

Explanation

This sentence contains the singular subject Great Plains but needs a verb. Answer D is the best answer because it contains the verb makes up. Answer A contains a present participle, answer B contains a prepositional phrase, and answer C contains an extra subject and a verb that is not logical, so these answers are incorrect.

15. Although Congress passed an income tax law in1894, in 1895 ______ the law unconstitutional.

A) the ruling of the Supreme Court

B) was ruled by the Supreme Court

C) if the Supreme Court ruled

D) the Supreme Court ruled

This sentence has an adverb clause Although Congress passed… and an incomplete main clause … the law unconstitutional. The incomplete clause needs a subject and a verb to be complete. Answer D is the best answer because it contains the subject Supreme Court and the verb ruled. Answer A is missing a verb, answer B is missing a subject, and answer C contains a conditional connector, so these answers are incorrect.

Explanation

This sentence has an adverb clause Although Congress passed… and an incomplete main clause … the law unconstitutional. The incomplete clause needs a subject and a verb to be complete. Answer D is the best answer because it contains the subject Supreme Court and the verb ruled. Answer A is missing a verb, answer B is missing a subject, and answer C contains a conditional connector, so these answers are incorrect.

16. ______ long enough, every Down's syndrome individual gets Alzheimer's disease.

The person lives

If the person living

If the person lives

Because the life

This sentence has a complete main clause every Down’s syndrome individual gets… and an incomplete adverb clause … long enough. The adverb clause needs a connector, a subject, and a verb to be complete. Answer C is the best answer because it contains the connector If, the subject person, and the verb lives. Answer A is missing a connector, answer B contains a present participle, and answer D is missing a verb. So these answers are incorrect.

Explanation

This sentence has a complete main clause every Down’s syndrome individual gets… and an incomplete adverb clause … long enough. The adverb clause needs a connector, a subject, and a verb to be complete. Answer C is the best answer because it contains the connector If, the subject person, and the verb lives. Answer A is missing a connector, answer B contains a present participle, and answer D is missing a verb. So these answers are incorrect.

17. ________ alcoholism are the slow destruction of the liver and possible death.

Dangerously

The eventual effect of

The long-term effects of

Chronic and eventual

This sentence contains a verb are but needs a plural subject and preposition for the object alcoholism. Answer C is the best answer because it contains the subject effects and the preposition of. Answer A contains an adverb, answer B contains a singular subject, and answer D contains two adjectives, so these answers are incorrect.

Explanation

This sentence contains a verb are but needs a plural subject and preposition for the object alcoholism. Answer C is the best answer because it contains the subject effects and the preposition of. Answer A contains an adverb, answer B contains a singular subject, and answer D contains two adjectives, so these answers are incorrect.

18. Humans living at high elevations ______ to the lower of oxygen in the air by producing more red blood corpuscles.

Adjust

To adjust

The adjustment

Adjusting

This sentence contains a subject Humans but needs a verb; living is a present participle used as an adjective and is not the verb. Answer A is the best answer because it contains the verb adjust. Answer B contains an infinitive, answer C contains a noun, and answer D contains a present participle, so these answers are incorrect.

Explanation

This sentence contains a subject Humans but needs a verb; living is a present participle used as an adjective and is not the verb. Answer A is the best answer because it contains the verb adjust. Answer B contains an infinitive, answer C contains a noun, and answer D contains a present participle, so these answers are incorrect.

19. The reservoir created by the Three Gorges Dam will flood almost 1400 villages, ______ to relocate the villages' nearly two million inhabitants

The government plans

So the governments plans

So the government plans

The governments plans

This sentence has a complete main clause The reservoir… will flood… and an incomplete main clause … to relocate the villages’… The incomplete main clause needs a subject and a verb to be complete, and the two clauses must be joined by a coordinate connector. Answer C is the best answer because it contains the coordinate connector so, the subject the government, and the verb plans. Answer A is missing a coordinate connector, answer B is missing a verb, and answer D is missing a coordinate connector and a verb, so these answers are incorrect.

Explanation

This sentence has a complete main clause The reservoir… will flood… and an incomplete main clause … to relocate the villages’… The incomplete main clause needs a subject and a verb to be complete, and the two clauses must be joined by a coordinate connector. Answer C is the best answer because it contains the coordinate connector so, the subject the government, and the verb plans. Answer A is missing a coordinate connector, answer B is missing a verb, and answer D is missing a coordinate connector and a verb, so these answers are incorrect.

20. During the Middle Ages, ______, large sets of bells with as many as 70 bells, first became popular.

With carillons

Carillons are

Carillons have

Carillons

This sentence contains a verb became but needs a subject; the commas show that …sets… is an appositive and is not the subject. Answer D is the best answer because it contains the subject carillons. Answer A contains a prepositional phrase, and answer B and C each contain an extra verb, so these answers are incorrect.

Explanation

This sentence contains a verb became but needs a subject; the commas show that …sets… is an appositive and is not the subject. Answer D is the best answer because it contains the subject carillons. Answer A contains a prepositional phrase, and answer B and C each contain an extra verb, so these answers are incorrect.

21. The Mayflower Compact, signed by the Pilgrims upon their arrival in Massachusetts in 1620, ______ their political and religious beliefs.

The statement of

Stating

With a statement of

Stated

This sentence contains a subject Mayflower Compact but needs a verb; signed is a past participle used as an adjective and is not the verb. Answer D is the best answer because it contains the verb stated. Answer A contains a noun, answer B contains a present participle, and answer C contains a prepositional phrase, so these answers are incorrect.

Explanation

This sentence contains a subject Mayflower Compact but needs a verb; signed is a past participle used as an adjective and is not the verb. Answer D is the best answer because it contains the verb stated. Answer A contains a noun, answer B contains a present participle, and answer C contains a prepositional phrase, so these answers are incorrect.

22. ______, Jesse Owens won four gold medals at the 1936 Olympics in Berlin.

Excellent speed and running ability

The outstanding track athlete runs

An outstanding track athlete

He had excellent speed and running ability

This sentence contains a subject Jesse Owens and a verb won; an appositive can be added before the comma. Answer C is the best answer because it contains the appositive track athlete. Answer A contains an appositive that is not logical with a person, and answers B and D each contain an extra subject and verb, so these answers are incorrect.

Explanation

This sentence contains a subject Jesse Owens and a verb won; an appositive can be added before the comma. Answer C is the best answer because it contains the appositive track athlete. Answer A contains an appositive that is not logical with a person, and answers B and D each contain an extra subject and verb, so these answers are incorrect.

23. On November 19, 1863, Abraham Lincoln, speaking from notes on an old ________ the famous Gettysburg Address in only two minutes time.

Gave the envelope

Envelope giving

Envelope, gave

Gift of an envelope

This sentence contains a subject Abraham Lincoln but needs an object of the preposition on and a verb. Answer C is the best answer because it contains the object envelope and the verb gave. Answer A contains a verb and its object, answer B contains a noun followed by a past participle, and answer D is missing a verb, so these answers are incorrect.

Explanation

This sentence contains a subject Abraham Lincoln but needs an object of the preposition on and a verb. Answer C is the best answer because it contains the object envelope and the verb gave. Answer A contains a verb and its object, answer B contains a noun followed by a past participle, and answer D is missing a verb, so these answers are incorrect.

24. The tea plant, an evergreen shrub pruned to three to five feet high, ______ mild, semitropical climate in which to grow.

The need for

It needs

To need

Needs a

This sentence contains a subject tea plant but needs a verb; pruned is a past participle used as an adjective and is not the verb. Answer D is the best answer because it contains the verb needs. Answer A contains a noun, answer B contains an extra subject, and answer C contains an infinitive, so these answers are incorrect.

Explanation

This sentence contains a subject tea plant but needs a verb; pruned is a past participle used as an adjective and is not the verb. Answer D is the best answer because it contains the verb needs. Answer A contains a noun, answer B contains an extra subject, and answer C contains an infinitive, so these answers are incorrect.

25. The _______ during an earthquake are caused by seismic waves.

Actually vibrate

Actual vibrations

Vibrations happen

From the actual vibrations

This sentence contains a verb are but needs a subject; earthquake is the object of the preposition during and is not the subject. Answer B is the best answer because it contains the subject vibrations. Answer A contains a verb, answer C contains an extra verb, and answer D contains a prepositional phrase, so these answers are incorrect.

Explanation

This sentence contains a verb are but needs a subject; earthquake is the object of the preposition during and is not the subject. Answer B is the best answer because it contains the subject vibrations. Answer A contains a verb, answer C contains an extra verb, and answer D contains a prepositional phrase, so these answers are incorrect.

26. ______ dugout canoes where the floodplains have dried into long stretches of dry sand.

Because oxen pull

Oxen pull

For oxen to pull

Oxen pulling

This sentence has a complete adverb clause where the floodplains have dried… and an incomplete main clause… dugout canoes. The main clause needs a subject and a verb to be complete. Answer B is the best answer because it contains the subject Oxen and the verb pull. Answer A contains an adverb clause connector, answer C contains a prepositional phrase and an infinitive, and answer D contains a present participle, so these answers are incorrect.

Explanation

This sentence has a complete adverb clause where the floodplains have dried… and an incomplete main clause… dugout canoes. The main clause needs a subject and a verb to be complete. Answer B is the best answer because it contains the subject Oxen and the verb pull. Answer A contains an adverb clause connector, answer C contains a prepositional phrase and an infinitive, and answer D contains a present participle, so these answers are incorrect.

27. Caffeine is primarily consumed in coffee and tea, _____ also found in cocoa, cola, and other soft drinks

But

But it

But it is

It is

This sentence has a complete main clause Caffeine is… consumed… and an incomplete main clause … also found in… The incomplete clause needs a subject and a helping verb to be complete, and the sentence needs a coordinate connector to join the two clauses. Answer C is the best answer because it contains the subject it, the helping verb is, and the coordinate connector but. Answer A is missing a subject and a helping verb, answer B is missing a helping verb, and answer D is missing a coordinate connector, so these answers are incorrect.

Explanation

This sentence has a complete main clause Caffeine is… consumed… and an incomplete main clause … also found in… The incomplete clause needs a subject and a helping verb to be complete, and the sentence needs a coordinate connector to join the two clauses. Answer C is the best answer because it contains the subject it, the helping verb is, and the coordinate connector but. Answer A is missing a subject and a helping verb, answer B is missing a helping verb, and answer D is missing a coordinate connector, so these answers are incorrect.

28. _______ walking properly and has enough area to walk in, it should wear down the hoof as it regrows.

If the animal is

The animal is

Although the animal

Although

This sentence has a complete main clause it should wear down… and an incomplete adverb clause … walking properly and has enough area… The adverb clause needs a subject, a verb, and a connector to be complete. Answer A is the best answer because it contains the subject the animal, the verb is, and the connector If. Answer B is missing a connector, answer C is missing a verb, and answer D is missing a subject and a verb, so these answers are incorrect.

Explanation

This sentence has a complete main clause it should wear down… and an incomplete adverb clause … walking properly and has enough area… The adverb clause needs a subject, a verb, and a connector to be complete. Answer A is the best answer because it contains the subject the animal, the verb is, and the connector If. Answer B is missing a connector, answer C is missing a verb, and answer D is missing a subject and a verb, so these answers are incorrect.

29. When San Diego's summer heat has withered most flowers, ______ bloom.

As soon as lilies

Lilies

Of lilies

By the time lilies start

This sentence contains a complete adverb clause When San Diego’s summer heat has withered… and an incomplete main clause… bloom. The main clause needs a subject to be complete. Answer B is the best answer because it contains the subject lilies. Answers A and D both contain an adverb time connector, and answer C contains a prepositional phrase, so these answers are incorrect.

Explanation

This sentence contains a complete adverb clause When San Diego’s summer heat has withered… and an incomplete main clause… bloom. The main clause needs a subject to be complete. Answer B is the best answer because it contains the subject lilies. Answers A and D both contain an adverb time connector, and answer C contains a prepositional phrase, so these answers are incorrect.

30. Champagnecan be purchased by Balthazar, ______ cannot be purchased in this amount.

Brandy

But

Because brandy

But brandy

This sentence has a complete main clause Champagne can be purchased… and an incomplete main clause cannot be purchased… The incomplete clause needs a subject and a coordinate connector to be complete. Answer D is the best answer because it contains the connector but and the subject brandy. Answer A is missing a coordinate connector, answer B is missing a subject, and answer C contains an adverb connector, so these answers are incorrect.

Explanation

This sentence has a complete main clause Champagne can be purchased… and an incomplete main clause cannot be purchased… The incomplete clause needs a subject and a coordinate connector to be complete. Answer D is the best answer because it contains the connector but and the subject brandy. Answer A is missing a coordinate connector, answer B is missing a subject, and answer C contains an adverb connector, so these answers are incorrect.

31. Gustave Eiffel is famous for building the Eiffel Tower, ______ for designing the framework of the Statue of Liberty.

He is remembered

Is remembered

Yet he is seldom remembered

Yet remembered

This sentence has a complete main clause Gustave Eiffel is famous… and an incomplete main clause… for designing the framework of the Statue of Liberty. The incomplete clause needs a subject and a verb to be complete, and the two clauses need a coordinate connector to join them. Answer C is the best answer because it contains the coordinate connector yet, the subject he, and the verb is… remembered. Answer A is missing a coordinate connector, answer B is missing a coordinate connector and a subject, and answer D is missing a subject, so these answers are incorrect.

Explanation

This sentence has a complete main clause Gustave Eiffel is famous… and an incomplete main clause… for designing the framework of the Statue of Liberty. The incomplete clause needs a subject and a verb to be complete, and the two clauses need a coordinate connector to join them. Answer C is the best answer because it contains the coordinate connector yet, the subject he, and the verb is… remembered. Answer A is missing a coordinate connector, answer B is missing a coordinate connector and a subject, and answer D is missing a subject, so these answers are incorrect.

32. The _______, the first daily newspaper in the United States, first appeared in 1793.

Two- page Pennsylvania Evening Post

Pennsylvania evening Post is two pages long

Pennsylvania Evening Post was

Two- page Pennsylvania Evening Post’s

This sentence contains the verb appeared but needs a subject; the commas show that newspaper is an appositive and is not the subject. Answer A is the best answer because it contains the subject Pennsylvania Evening Post. Answers B and C each contain an extra verb, and answer D contains a possessive adjective, so these answers are incorrect.

Explanation

This sentence contains the verb appeared but needs a subject; the commas show that newspaper is an appositive and is not the subject. Answer A is the best answer because it contains the subject Pennsylvania Evening Post. Answers B and C each contain an extra verb, and answer D contains a possessive adjective, so these answers are incorrect.

33. Parent flamingos lose their intense pink coloring until ______.

Weaning young

Their youths

They wean their young

Young

This sentence has a main clause Parent flamingos lose… and an incomplete adverb clause until… The adverb clause needs a subject and a verb to be complete. Answer C is the best answer because it contains the subject and verb they wean. Answer A contains a present participle, answer B is missing a verb, and answer D contains an adjective, so these answers are incorrect.

Explanation

This sentence has a main clause Parent flamingos lose… and an incomplete adverb clause until… The adverb clause needs a subject and a verb to be complete. Answer C is the best answer because it contains the subject and verb they wean. Answer A contains a present participle, answer B is missing a verb, and answer D contains an adjective, so these answers are incorrect.

34. Further changes in the celestial constellations ______ the International Astronomical Union has been formed

Are unlike now that

Unlike whenever

Are unlikely

The are unlikely

This sentence has an incomplete main clause Further changes… and an adverb clause the International Astronomical Union has been formed. The main clause needs a verb t be complete, and the two clauses need a connector to join them. Answer A is the best answer because it contains the verb are and the connector now that. Answer B is missing a verb, and answers C and D are each missing a connector, so these answers are incorrect.

Explanation

This sentence has an incomplete main clause Further changes… and an adverb clause the International Astronomical Union has been formed. The main clause needs a verb t be complete, and the two clauses need a connector to join them. Answer A is the best answer because it contains the verb are and the connector now that. Answer B is missing a verb, and answers C and D are each missing a connector, so these answers are incorrect.

35. A little fat is essential for humans______ retain body heat, gives muscles energy, and keeps skin soft.

As it helps

Although it

It helps

In helping

This sentence has a complete main clause A little fat is essential… and an incomplete adverb clause… retain body heat, gives muscles energy, and keeps skin soft. The adverb clause needs a subject and a connector to be complete. Answer A is the best answer because it contains the connector as and the subject it. Answer B contains a subject that does not agree with the verb retain. Answer C is missing a connector, and answer D contains a prepositional phrase, so these answers are incorrect.

Explanation

This sentence has a complete main clause A little fat is essential… and an incomplete adverb clause… retain body heat, gives muscles energy, and keeps skin soft. The adverb clause needs a subject and a connector to be complete. Answer A is the best answer because it contains the connector as and the subject it. Answer B contains a subject that does not agree with the verb retain. Answer C is missing a connector, and answer D contains a prepositional phrase, so these answers are incorrect.

36. Change, both good and bad, can create stress, ______, if sufficiently severe, can lead to illness.

And stress

And stressed

Stress

That stress

This sentence has a complete main clause Change… can create stress and an incomplete main clause … can lead to illness. The incomplete clause needs a subject to be complete, and the two clauses need a coordinate connector to join them. Answer A is the best answer because it contains the subject stress and the coordinate connector and. Answer B is missing a subject, and answers C and D are each missing a coordinate connector, so these answers are incorrect.

Explanation

This sentence has a complete main clause Change… can create stress and an incomplete main clause … can lead to illness. The incomplete clause needs a subject to be complete, and the two clauses need a coordinate connector to join them. Answer A is the best answer because it contains the subject stress and the coordinate connector and. Answer B is missing a subject, and answers C and D are each missing a coordinate connector, so these answers are incorrect.

37. Thomas Jefferson, _______ a personally designed and constructed lap-top desk, wrote the Declaration of Independence in the summer of 1776.

He used

Had used

The use of

Using

This sentence contains a subject Thomas Jefferson and a verb wrote; a present participle can be used after the subject. Answer D is the best answer because it contains the present participle using. Answer A contains an extra subject and verb, answer B contains an extra verb, and answer C contains an appositive that is not logical with a person, so these sentences are incorrect.

Explanation

This sentence contains a subject Thomas Jefferson and a verb wrote; a present participle can be used after the subject. Answer D is the best answer because it contains the present participle using. Answer A contains an extra subject and verb, answer B contains an extra verb, and answer C contains an appositive that is not logical with a person, so these sentences are incorrect.

38. ______ can consume 30000 plant species, 90percent of the human diet consists of only 20 of the available species

Humans

In contrast humans

Providing for humans

While humans

This sentence has a complete main clause 90 percent… consists… and an incomplete adverb clause …can consume… To be complete, the adverb clause needs a subject and a connector. Answer D is the best answer because it contains the connector While and the subject humans. Answers A and C are each missing a connector, and answer B contains an adverb transition, so these answers are incorrect

Explanation

This sentence has a complete main clause 90 percent… consists… and an incomplete adverb clause …can consume… To be complete, the adverb clause needs a subject and a connector. Answer D is the best answer because it contains the connector While and the subject humans. Answers A and C are each missing a connector, and answer B contains an adverb transition, so these answers are incorrect

39. Like a mountain, the Empire State Building creates its own updrafts, ______ have been observed to fall up.

And snow and rain

Snow and rain

Of snow

This sentence contains a complete main clause the Empire State Building creates… and an incomplete main clause… have been observed… The incomplete clause needs a plural subject and a coordinate connector to join the tow clauses. Answer A is the best answer because it contains the coordinate connector and and the plural subject snow and rain. Answer B is missing a coordinate connector, answer C contains a prepositional phrase, and answer D contains a singular subject, so these answers are incorrect.

Explanation

This sentence contains a complete main clause the Empire State Building creates… and an incomplete main clause… have been observed… The incomplete clause needs a plural subject and a coordinate connector to join the tow clauses. Answer A is the best answer because it contains the coordinate connector and and the plural subject snow and rain. Answer B is missing a coordinate connector, answer C contains a prepositional phrase, and answer D contains a singular subject, so these answers are incorrect.

40. ______ perceives the color black provided there is a complete lack of stimulation of the retina.

When a person

A person will

If a person

A person

This sentence contains a complete adverb clause provided there is a complete lack… and an incomplete main clause. The main clause needs a subject to be complete. Answer D is the best answer because it contains the subject person. Answer A contains an extra noun clause connector, answer B contains an extra verb, and answer C contains an extra adverb connector, so these answers are incorrect.

Explanation

This sentence contains a complete adverb clause provided there is a complete lack… and an incomplete main clause. The main clause needs a subject to be complete. Answer D is the best answer because it contains the subject person. Answer A contains an extra noun clause connector, answer B contains an extra verb, and answer C contains an extra adverb connector, so these answers are incorrect.