My mother isn’t in, I must ___ my sister at home.
A. look at B. look after C. look up
―Congratulations, Jane, you have won the first prize in the physics competition.
―Thank you, Mr Green. I can’t make such great __________ without your help.
| A．experience | B．experiment |
| C．progress | D．operation |
The water in the river nearby will be dirtier than before if nothing __________.
| A．has done | B．will be done |
| C．is done | D．was done |
―Is Tom coming to the concert this evening?
―No, he _________ be at the concert. He _______ abroad.
| A．mustn’t, has been | B．mustn’t, has been to |
| C．can’t, has gone to | D．can’t, has gone |
Foreign visitors will get lost easily in new Taixing ________ they have a map.
| A．until | B．if |
| C．whether | D．unless |
―What can I do for you?
―__________.
| A．I’m looking for a tie for my father |
| B．Yes, you can give a tie to me |
| C．No, I can do it myself |
| D．I can do what I want |