There are two types of Writing questions:
IDENTIFYING SENTENCE ERROR QUESTIONS
Identifying Sentence Error (ISE) Questions test your ability to recognize grammar and usage errors. Each sentence contains either a single error or no error at all. You will not encounter any sentences that contain more than one error. If the sentence contains an error, select the one underlined part (choices A through D) that must be changed to make the sentence correct. If the sentence is correct choose choice E - no error. The following is a sample ISE question:
For this particular question, you would select choice D because the sentence references Mark Twain's novels, which is plural. Therefore a storyline should instead be storylines.
CORRECT THE SENTENCE QUESTIONS
Correct the Sentence (CTS) Questions test correctness and effectiveness of expression. A portion of each sentence (sometimes the entire sentence) is underlined. Each question has 5 answer choices from which to choose. Choice A will always repeat the original phrasing and should be picked whenever a sentence contains no errors. Choices B through E suggest four different ways the sentence could be written. If you decide there is an error, you must then decide which choice among B, C, D, and E is best.
The following is a sample CTS:
For this particular question, you would select choice D. They pulled one of their favorite tricks here - put a plural subject (four downtown bistro locations) that is not the active subject of the verb right next to the active verb (were) hoping that you will look at the verb were and think it's correct given that it sits next to a plural subject.
But, the actual subject of the verb were is the all you can eat special, which is singular - so were should be changed to was.