Don’t __________ at your parents. It’s impolite (不礼貌的).—Sorry, I will not.

Your uncle seems to be a good driver; _____, I wouldn’t dare to travel in his car[ ]

It was the middle of the night _______ my father woke me up and told me to watch the football game.

income worry is _______ rather common problem of the aged, loneliness is another problem that _______ aged parents may face.

Can you tell me how much___________________