They kept trying _____ they must have known it was hopeless.
| A．if | B．because | C．when | D．where |
I was really anxious about you. You ________ home without a word.
| A．mustn’t leave | B．shouldn’t have left |
| C．couldn’t have left | D．needn’t leave |
Tom ought not to ________ me your secret, but he meant no harm.
| A．have told | B．tell |
| C．be telling | D．having told |
We ________ last night, but we went to the concert instead.
| A．must have studied | B．might study |
| C．should have studied | D．would study |
—I’ll tell Mary about her new job tomorrow.
—You ________ her last week.
| A．ought to tell | B．would have told |
| C．must tell | D．should have told |
On Sundays there were a lot of children playing in the park, and _______ parents were seated together joking.
| A．their | B．whose |
| C．which | D．that |