Section H: Last Comma Rule (Practice)

Explanation
The given statement is a repetition of the same sentence. It states that the car with a broken tail light belongs to the speaker. The repetition emphasizes this fact and reinforces the ownership of the car.

Explanation
This statement is a repetition of the given information. It simply restates that the apples in the refrigerator are organic.

Explanation
The correct answer is "The apple in my hand, which is organic, is a red delicious." This answer is correct because it correctly uses commas to set off the nonessential clause "which is organic." The clause provides additional information about the apple but is not necessary for the sentence's main meaning. The use of commas indicates that the information is not essential and can be removed without changing the overall meaning of the sentence.

Explanation
This statement is a repetition of the given information. It simply states that the woman who is waving at "us" is the speaker's aunt.

Explanation
The correct answer is "That woman, who happens to be my aunt, is taking us out for lunch." The use of commas in this sentence is necessary to provide additional information about the woman. The phrase "who happens to be my aunt" is a nonessential clause that adds extra detail but can be removed without changing the meaning of the sentence. The commas indicate that this information is not essential to understanding the main idea of the sentence, which is that the woman is taking them out for lunch.

Explanation
The correct answer is "This child, who has been screaming for ten minutes, has very poor manners." The explanation is that the phrase "who has been screaming for ten minutes" is a nonrestrictive clause, providing additional information about the child. It is set off by commas to indicate that it is not essential to the meaning of the sentence. The main point of the sentence is that the child has very poor manners, and the nonrestrictive clause adds further detail about the child's behavior.

Explanation
Helium is a lighter-than-air gas, which means it has a lower density than the surrounding air. When a balloon is filled with helium, the gas inside the balloon is less dense than the air outside. This causes the balloon to become buoyant and float upwards. If you let go of the balloon, there is no force holding it down, so it will continue to rise until it reaches a point where the density of the surrounding air matches the density of the helium inside the balloon. At this point, the balloon will float at a stable height in the atmosphere.

Explanation
The correct answer is "Your bike, which is a Trek, is locked up in our garage." This answer correctly uses commas to set off the nonessential information "which is a Trek." This additional information provides extra detail about the bike, but it is not necessary for understanding the main message of the sentence, which is that the bike is locked up in the garage.

Explanation
The given sentence is a repetition of the same statement. It states that Doug's shirt, which got stained, is currently soaking.

Explanation
This statement is a repetition of the given information. It simply restates that the cell phone which is ringing is located in someone's locker.

Explanation
The given answer simply restates the information provided in the question. It confirms that the doughnut with mold on it has been sitting there for a week.

Explanation
The correct answer is "This year’s band fundraiser, which involves selling pizza, will begin next week." The explanation for this answer is that the phrase "which involves selling pizza" is a nonrestrictive clause that provides additional information about the band fundraiser. It is set off by commas because it is not essential to the meaning of the sentence. The sentence could still make sense without this clause, but the additional information adds context and detail.