---Is there ___ you don't understand?---I think ___ is quite clear.Thank you.

 —Life is hard these days.—At least we have some money left. That's ________, isn't it?

—What do you think of your college life?—Tired! __ win the scholarship(奖学金), I have made a full schedule(时间表) for study.

The boy doesn’t like ______ when his mother compares him with the other children in the neighborhood.

Cook was a strict but good captain , _____ who , usually , took care of the sailors on his trip .