It was not until the teacher had explained it three times _______ how to work out the problem.
| A．did he understand | B．had he understood |
| C．that he understood | D．that he didn’t understood |
The doctors did all theythe sick man back to life.
| A．could bring | B．could to bring | C．could bringing | D．cuold to bringing |
As we grow older,we learn theof our abilities.
| A．heights | B．scores | C．limits | D．lengths |
1．! There is a train coming．
| A．Look out | B．Look around |
| C．Look forward | D．Look on |
9.―Your job ____ open for your return.
―Thanks.
| A．will be kept | B．will keep |
| C．had kept | D．had been kept |
8.Customers are asked to make sure that they ____ the right change before leaving the shop.
| A．will give | B．have been given |
| C．have given | D．will be given |