Main Idea Exercises

1. Basketball was invented in 1891 by a physical education instructor in Springfield, Massachusetts, by the name of James Naismith. Because of the terrible weather in winter, his physical education students were indoors rather than outdoors. They really did not like the idea of boring, repetitive exercises and preferred the excitement and challenge of a game. Naismith figured out a team sport that could be played indoors on a gymnasium floor, that involved a lot of running, that kept all team members involved, and that did not allow the tackling and physical contact of American-style football. Question: What is the main idea of the passage?

The life of James Naismith

The history of sports

Physical education and exercise

The origin of basketball

The first sentence of this passage discusses the invention of basketball, so this is probably the topic. A quick check of the rest of the sentences in the passage con firms that the topic is in fact the beginnings of the sport of basketball. Now you should check each of the answers to determine which one comes closest to the topic that you have determined. Answer (A) mentions James Naismith but not basketball, so it is not the topic. Answer (B) is too general; it mentions sports but does not mention basketball. Answer (C) is also too general; it mentions physical education but does not mention basketball. The best answer is therefore answer (D); the origin of basketball means that the invention of basketball is going to be discussed.

Explanation

The first sentence of this passage discusses the invention of basketball, so this is probably the topic. A quick check of the rest of the sentences in the passage con firms that the topic is in fact the beginnings of the sport of basketball. Now you should check each of the answers to determine which one comes closest to the topic that you have determined. Answer (A) mentions James Naismith but not basketball, so it is not the topic. Answer (B) is too general; it mentions sports but does not mention basketball. Answer (C) is also too general; it mentions physical education but does not mention basketball. The best answer is therefore answer (D); the origin of basketball means that the invention of basketball is going to be discussed.

2. Strictly speaking, cartography is the drawing or compiling of maps. The explorers and surveyors go out and make the measurements and gather the information from which the cartographers draw their maps. Sometimes the fieldwork and the creation of the map are done by the same person. But when the scope is broad and the sources of information many, maps are more often a compilation of that information. They represent the accumulated work of many people, brought together under the supervision of one person, the compiler. The value of the map depends, of course, on the expertise of the compiler, who must sift through available information, select the most accurate data, and come up with a thoughtful and accurate synthesis of geographic knowledge of the region. What is the main idea of the passage?

The definition of cartography is the drawing or compiling of maps.

Maps are the product of a group effort brought together usually by one person.

Not all of the information initially compiled for maps is accurate.

The compiler’s task is more important than that of the explorers and surveyors.

The passage explains that cartography involves the drawing or compiling of maps, and that maps are often a compilation of information gathered by explorers and surveyors. The main idea of the passage is that maps are the product of a group effort, brought together under the supervision of one person, the compiler. This person's expertise is important in selecting accurate data and creating a thoughtful and accurate synthesis of geographic knowledge.

Explanation

The passage explains that cartography involves the drawing or compiling of maps, and that maps are often a compilation of information gathered by explorers and surveyors. The main idea of the passage is that maps are the product of a group effort, brought together under the supervision of one person, the compiler. This person's expertise is important in selecting accurate data and creating a thoughtful and accurate synthesis of geographic knowledge.

3. Because different tree species adapted to different climates and soil types have evolved over millennia, many kinds of forests occupy the earth today. The primitive forests of several hundred million years ago consisted of fewer kinds of trees. In fact, the earliest "trees", which grew nearly 500 million years ago, were like giant club mosses. They lacked true roots and consisted of a tangle of specialized branches that clambered over rocky ground. Fifty million years later came the dense forest of tree ferns that prevailed in tropical climates of that era. The forerunners of modern conifers were on the scene 300 million years ago, when plant life abundantly colonized marshy land, building the tremendous coal and oil reserves so important today. By the time the dinosaurs roamed the earth some 180 million years ago, during the Cretaceous period, seed- bearing trees had evolved that shed their leaves in winter; from these have sprung the angiosperms and our present deciduous forests. What is the main idea of the passage?

Conifers are the oldest trees in today’s forests.

Climate affected the development of trees over millennia.

The predecessors of today’s forests were giant club mosses and tree ferns.

The varieties of trees in today’s forest are a result of millions of years of evolution.

The main idea of the passage is that the varieties of trees in today's forest are a result of millions of years of evolution. The passage discusses how different tree species adapted to different climates and soil types over time, leading to the development of various kinds of forests on Earth. It mentions the primitive forests consisting of fewer kinds of trees, the evolution of different types of trees such as giant club mosses, tree ferns, conifers, and seed-bearing trees, and how these developments have led to the present diversity of trees in forests.

Explanation

The main idea of the passage is that the varieties of trees in today's forest are a result of millions of years of evolution. The passage discusses how different tree species adapted to different climates and soil types over time, leading to the development of various kinds of forests on Earth. It mentions the primitive forests consisting of fewer kinds of trees, the evolution of different types of trees such as giant club mosses, tree ferns, conifers, and seed-bearing trees, and how these developments have led to the present diversity of trees in forests.

4. Hawaii was originally settled by the natives of the South Pacific, who arrived in the islands in canoes laden with breadfruit, yams, taro, coconut, bananas, pigs, and chickens. Supplementing these foods were over a hundred different edible fishes and forty kinds of seaweed from the surrounding waters. Hawaiian food was eaten raw or wrapped in taro leaves, seasoned with coconut, and cooked. In the early 1800s, the whalers and missionaries introduced stews, chowders, curries, corned beef, dried beef, salt salmon, and Indian and cornstarch puddings. Most likely, pipkaula (jerked beef), lomi lomi salmon, and haupia (coconut pudding) evolved during this period. In the late nineteenth century immigrants from China, Japan, and Korea were brought to Hawaii to work the sugar plantations. The Chinese brought rice, soybeans, and vegetables and their ways of cooking them. The Japanese brought sukiyaki and teriyaki, among many other foods. Settlers from the continental United States also brought their favorite recipes and in the spirit of aloha, the Hawaiians have accepted each group's offerings and drawn the best from them. Thus a Hawaiian feast is a gastronomic experience, the essence of Hawaii and its cultures. What is the main idea of the passage?

Whalers and missionaries introduced new kinds of foods to the people of Hawaii.

Sugar plantations were worked by immigrants from Asia, who brought their native foods with them.

Hawaiian food is a combination of the foods of many peoples and a reflection of Hawaii’s history.

The natives of the South Pacific who first settled in Hawaii ate raw food, whereas other immigrants cooked theirs.

The main idea of the passage is that Hawaiian food is a combination of the foods of many peoples and a reflection of Hawaii's history. The passage discusses how the natives of the South Pacific settled in Hawaii and brought their own foods, how whalers and missionaries introduced new kinds of foods, and how immigrants from China, Japan, and Korea brought their native foods as well. It emphasizes that Hawaiian food is a fusion of these different culinary influences, making it a unique and diverse gastronomic experience.

Explanation

The main idea of the passage is that Hawaiian food is a combination of the foods of many peoples and a reflection of Hawaii's history. The passage discusses how the natives of the South Pacific settled in Hawaii and brought their own foods, how whalers and missionaries introduced new kinds of foods, and how immigrants from China, Japan, and Korea brought their native foods as well. It emphasizes that Hawaiian food is a fusion of these different culinary influences, making it a unique and diverse gastronomic experience.

5. Innovations in transportation in the 1800s permitted space to be traversed more rapidly and were crucial to the industrial expansion of the North. The great spaces that separated producers from consumers made speech essential, especially in the movement of perishable freight. The development of the steam-powered locomotive in the 1830s and the rapid extension of the railways in the 1840s and the 1850s provided the answer to the need for the faster transport and dramatically altered patterns of economic development throughout the United States. In 1830 there were 32 miles of rails in the country, in 1840 there were 2,818 miles, and by 1850 there were more than 9,000 miles. The rapid extension of rail mileage enabled the railroads significantly to reduce their costs for shipping freight and carrying passengers, thus enabling them to price their services more cheaply and competitively. The extension of trunk lines, into which short or local lines fed, further tightened the east-west flow of commerce and bound the Northeast and the old Northwest together with bands of steel. What is the main theme in the passage?

Railroad made the transportation of perishable freight possible.

Between 1830 and 1850 over 8,000 miles of railroad track were laid.

Railroads provided an important link between the Northwest and the Northeast.

Railroads had a profound effect on the economic development of the United States in the nineteenth century.

The main theme in the passage is that railroads had a profound effect on the economic development of the United States in the nineteenth century. The passage discusses how innovations in transportation, specifically the development and rapid extension of railroads, played a crucial role in the industrial expansion of the North. It highlights the significant increase in rail mileage and how it enabled the railroads to reduce costs, ship freight more efficiently, and connect different regions of the country. This demonstrates the transformative impact of railroads on the economy during that time period.

Explanation

The main theme in the passage is that railroads had a profound effect on the economic development of the United States in the nineteenth century. The passage discusses how innovations in transportation, specifically the development and rapid extension of railroads, played a crucial role in the industrial expansion of the North. It highlights the significant increase in rail mileage and how it enabled the railroads to reduce costs, ship freight more efficiently, and connect different regions of the country. This demonstrates the transformative impact of railroads on the economy during that time period.

6. Speculation about the earth's crust has a special edge of urgency in California, which sits on the San Andreas fault, the world's most famous and respected fracture zone. Not surprisingly, it was scientist at the California Institute of Technology, Charles F. Richter, who invented the Richer scale used to measure earthquakes. Seismic activity in California is being constantly monitored and mapped. Seismometers register many thousands of small earthquakes every year, and computers instantly calculate the location, depth, and magnitude of an earthquake. Laser distance-ranging networks can detect changes of length, indicating change in crustal stress, accurate to about half an inch in 20 miles. Satellite measurements of crustal blocks are improving, and California seismologists believe they may in time be precise enough to allow earthquake prediction. What is the main idea expressed in the passage?

The Richer scale was invented in California.

Computers provide a variety of information about earthquakes.

A great deal of attention is paid to earthquake activity in California.

Earthquake prediction will be possible in the future.

The main idea expressed in the passage is that a great deal of attention is paid to earthquake activity in California. This is evident from the information provided about the monitoring and mapping of seismic activity, the invention of the Richer scale to measure earthquakes, and the advancements in technology to detect changes in crustal stress. The passage emphasizes the urgency and importance of understanding earthquake activity in California due to its location on the San Andreas fault. It also mentions the belief of California seismologists that earthquake prediction may be possible in the future.

Explanation

The main idea expressed in the passage is that a great deal of attention is paid to earthquake activity in California. This is evident from the information provided about the monitoring and mapping of seismic activity, the invention of the Richer scale to measure earthquakes, and the advancements in technology to detect changes in crustal stress. The passage emphasizes the urgency and importance of understanding earthquake activity in California due to its location on the San Andreas fault. It also mentions the belief of California seismologists that earthquake prediction may be possible in the future.

7. The few places left on earth that have not been altered by humankind are almost invariably hostile to humans. One such place is the Alaskan Arctic, which inhabited, where inhabited at all, by only a scattering of Eskimos, Native Americans, and whites. But while the Arctic is indeed a chill and inimical realm of snow, ice, and polar bears, it is also a region of great beauty and, above all, purity, where plants and animals still exist undisturbed in a state of natural balance. Nearly one third of Alaska lies north of the Arctic Circle and consists of pristine land. The Brooks Range cuts across the region like a wall, making access difficult. Even today, in an age of jet travel, the number of persons who have had firsthand experience in the Alaskan Arctic remains small, and countless valleys and mountains go unnamed and even unexplored. What is the primary topic of the passage?

The Alaskan Arctic is a beautifully pristine realm of snow, ice, and polar bears.

The Alaskan Arctic is habitable only to arctic animals and a few hardy humans.

The ruggedness of the Alaskan Arctic makes it one of the last few remaining pristine areas in the world.

Remarkably, parts of the Alaskan Arctic still remain unexplored.

The primary topic of the passage is that the ruggedness of the Alaskan Arctic makes it one of the last few remaining pristine areas in the world. The passage describes the harsh conditions and limited human presence in the Arctic, emphasizing its purity and natural balance. It also mentions that a significant portion of Alaska is untouched and inaccessible, and many parts of the region remain unexplored. This supports the idea that the Alaskan Arctic is one of the few remaining pristine areas on Earth.

Explanation

The primary topic of the passage is that the ruggedness of the Alaskan Arctic makes it one of the last few remaining pristine areas in the world. The passage describes the harsh conditions and limited human presence in the Arctic, emphasizing its purity and natural balance. It also mentions that a significant portion of Alaska is untouched and inaccessible, and many parts of the region remain unexplored. This supports the idea that the Alaskan Arctic is one of the few remaining pristine areas on Earth.

8. In the first half of the nineteenth century, the first distinctly American culture took form. The rise of an American tradition in literature paralleled the expansion of the nation, as American writers began to look within themselves and across their enlarged continental homeland for their subjects and themes. The romance, or novel, provided a useful form for dealing with the large moral subjects and the peculiar circumstances of the American setting. In James Fenimore Cooper's The Pioneers (1823) and The Deerslayer (1841), Natty Bumppo and the Mohican guide Chingachgook confronted the environment of the American frontier, chronicling the advance of "civilization" and questioning the implication of its impact on the natural world. The theme of the individual confronting nature was further developed by Herman Melville in the classic novel Moby Dick (1951). Nathaniel Hawthorne dealt with equally difficult questions of inner limits and the individual's responsibilities to society in The Scarlet Letter (1850) and The House of the Seven Gables (1851). What is the main idea of the passage?

As the nation expanded, novelists began writing about the American frontier.

The first American literature took the form of novels that dealt with uniquely American themes.

In their novels, Melville and Hawthorne both addressed difficult questions facing Americans.

The individual versus nature was one of the main themes explored in early American literature.

The passage discusses the rise of American literature in the first half of the nineteenth century, specifically focusing on the novel as a form of expression. It states that American writers began looking within themselves and their country for subjects and themes, and that the romance or novel provided a useful form for addressing moral subjects and the unique circumstances of the American setting. The passage mentions specific novels by James Fenimore Cooper, Herman Melville, and Nathaniel Hawthorne that explore themes such as civilization's impact on the natural world and the individual's responsibilities to society. Therefore, the main idea of the passage is that the first American literature took the form of novels that dealt with uniquely American themes.

Explanation

The passage discusses the rise of American literature in the first half of the nineteenth century, specifically focusing on the novel as a form of expression. It states that American writers began looking within themselves and their country for subjects and themes, and that the romance or novel provided a useful form for addressing moral subjects and the unique circumstances of the American setting. The passage mentions specific novels by James Fenimore Cooper, Herman Melville, and Nathaniel Hawthorne that explore themes such as civilization's impact on the natural world and the individual's responsibilities to society. Therefore, the main idea of the passage is that the first American literature took the form of novels that dealt with uniquely American themes.

9. Birds have two basic types of sounds: songs and calls. Songs are usually more complex than calls and are utilized primarily by adult males during the breeding season to establish territories or attract mates. Calls are normally simple notes, single or repeated, vocalized by males and females in all seasons to express alarm or maintain contacts with mates, offspring, or other birds of the same species. All song and most calls are distinctive, and with concentrated study and practice, bird-watchers can learn to identify many birds by their sounds and to call them as well. What is the main idea of the passage?

Bird calls and songs are distinctive, meaningful, and identifiable.

Bird songs are complicated and used mainly by males to attract mates.

Birds have their own language by which they maintain contact.

Bird-watchers can identify many bird calls and their meanings and learn to mimic them as well.

The main idea of the passage is that bird calls and songs are distinctive, meaningful, and identifiable. The passage explains that birds have two types of sounds: songs and calls. Songs are used by adult males during the breeding season to establish territories or attract mates, while calls are used by both males and females in all seasons to express alarm or maintain contact with other birds. The passage also mentions that with study and practice, bird-watchers can learn to identify many birds by their sounds and even mimic them. This supports the idea that bird calls and songs are distinctive, meaningful, and identifiable.

Explanation

The main idea of the passage is that bird calls and songs are distinctive, meaningful, and identifiable. The passage explains that birds have two types of sounds: songs and calls. Songs are used by adult males during the breeding season to establish territories or attract mates, while calls are used by both males and females in all seasons to express alarm or maintain contact with other birds. The passage also mentions that with study and practice, bird-watchers can learn to identify many birds by their sounds and even mimic them. This supports the idea that bird calls and songs are distinctive, meaningful, and identifiable.

10. In the 1820s and 1830s American painting added a new chapter to the story of its development. Until the 19^th century, portraiture and occasional historical pieces were the only concerns of American art, but throughout the 1800s some of America's most talented painters chose to depict landscapes the daily activities of ordinary people. With the nation's declaration of independence had come prosperity and with it the opportunity and inclination for painters to contemplate their environment. As they traveled beyond the early settlements and left the nation's first cities, such as Boston and Philadelphia, they began to experience and appreciate the pristine beauty of the American scenery, which differed greatly from the European landscape, partly because in its unsettled state it appeared wild and primeval. Question: What is the main topic of the passage?

Conditions in the early 1800s were favorable to the emergence of the American landscape artist.

In the early 1800s, landscapes were produced in preference to portraits and historical pieces.

America’s declaration of independence brought prosperity to the nation and with it an appreciation of the outdoors.

An increase in travel in America led to an appreciation of the beauty of the American landscape.

Conditions in the early 1800s like landscapes, environment., scenery created the appearance of the American landscape artists

Explanation

Conditions in the early 1800s like landscapes, environment., scenery created the appearance of the American landscape artists