7. C 8.D 9.D 10.A are The correct answer
Answer: The purpose of an excerpt is to be a trailer for a book.
Explanation: A excerpt can be like a little sneak peak that prepares the reader for the whole story. An excerpt can also help the the reader understand and memorize the subject the author is writing about.
The answer is "A" because of they were saying that they "were" reading on the plane. which is progressive tense.<span />