She showed the visitors around the museum, the construction had taken more than three years.
| A．for which | B．with which | C．of which | D．to which |
Let us play basketball, ______?
| A．will you | B．don’t we | C．shall we | D．do you |
Let’s clean our classroom, _____?
| A．will you | B．don’t we | C．shall we | D．do you |
Everyone _____ do his best for the modernizations of our country.
| A．can | B．may | C．should | D．might |
31. He _____ have come here yesterday, but he didn’t.
| A．could | B．should | C．ought to | D．all the above |
He ought to win the first prize, _____ he?
| A．oughtn’t | B．shouldn’t | C．mustn’t | D．both A and B |