Which of the following main idea of this excerpt from Kennedy's address at rice university?
I don't know your excerpt that was given you, but can give a general idea of his speech. He spoke about the nations space program and that "we choose to go to the moon."
An excerpt is a selected portion from a longer work such as a film or book. So long as you bear in mind its correct meaning, you can use the word "excerpt" in much the same way that you use the word "sample." The trailer shows an excerpt from the film "Avatar." The author read an excerpt from his new novel. I used an excerpt of the speech in my term paper.