How long do you think it will be _______ scientists succeed in providing a cure for cancer?
| A．when | B．after | C．since | D．before |
—How do you find that Beatles’CD?—Wonderful. It’s well worth ______.
| A．to listen to | B．listening to | C．to be listened to | D．being listened to |
—Shall I give you a ride as you live so far away？
—Thank you.___________.
| A．It couldn’t be better | B．Of course you can |
| C．If you like | D．It’s up to you. |
She was surprised to find the fridge empty；the children _____ everything !
| A．had been eating | B．had eaten |
| C．have eaten | D．have been eating |
There’s a ______in our office that when it’s somebody’s birthday，they bring in a cake for us all to share．
| A．tradition | B．balance | C．concern | D．relationship |
We've offered her the job，but I don’t know ____she’ll accept it．
| A．where | B．what | C．whether | D．which |