—Did you return the book on me? Why can’t I find it anywhere?—_______. You were writing a letter at your desk at that time.
Don’t bother Tom, he is ______ with the experiment on water molecules in the lab.
Nowadays some parents regret not ______ more time with their kids when they were young.
Have you heard that he, as well as his parents, ______ visited the Summer Palace? —Really? No ______ he didn’t attend the meeting.
Only ______ a human being.
Don’t ______ a person only because he has failed in an examination.