—Someone is knocking at the door. Is it Ann?
—It _____ be her. She is giving a performance at the theatre now.
| A．may | B．must | C．can’t | D．mustn’t |
—Can’t you stop making so much noise? I really can’t _____ it.
—I’m terribly sorry for giving you so much trouble.
| A．keep | B．stand | C．hear | D．make |
He said that he _____ to Canada a few years ago.
| A．had been to | B．have been to |
| C．went | D．go |
—We really shouldn’t use plastic bags any more when shopping.
—_____ It’s important to protect our environment.
| A．So do I. | B．With pleasure. |
| C．That’s OK. | D．So it is. |
Our country _____ progress in science and culture in recent years.
| A．made such | B．has made such |
| C．made so | D．has made so |
—What did our geography teacher say?
—She told us that the earth _____ around the sun.
| A．moves | B．moved |
| C．has moved | D．was moving |