In the Grand Canyon, each rock layer can __________ a chapter in a book.
The meeting is beginning at 8 o’clock. _____, let’s make some preparations for it.
Look! __________.
The suggestion that the president _____ the meeting was accepted.
_____ in 1936, Harvard is one of the most famous universities in the United States.
When you rewrite the paragraph, I advise you to _____ the last sentence as it is rather boring.