24.The students were ____ over the ____ problem, listening to the teacher with a ____ expression on their faces.
| A．puzzled; puzzling; puzzling | B．puzzled; puzzling; puzzled |
| C．puzzling; puzzling; puzzled | D．puzzling; puzzled; puzzling |
If I hadn’t been lucky enough to meet you. I really _____ what I would have done.
| A．don’t know | B．hadn’t known |
| C．wasn’t knowing | D．wouldn’t know |
“I still haven’t thanked Aunt Lucy for her present.” “It’s time you _____.”
| A．do | B．did |
| C．had | D．would |
_____ smoking, he would not have got cancer in the lung.
| A．Was he given up | B．Had he given up |
| C．Did he give | D．If he gave up |
I advised that he ______ to the hospital at once, but he insisted that he ______ quite well then.
| A．was sent; felt | B．be sent; was feeling |
| C．he sent; feel | D．should be sent; should feel |
The man in prison insisted that he _______ nothing wrong and _______ set free.
| A．should do, should be | B．had done, should be |
| C．had done, had been | D．should do, had been |