------Don't put the waste on the ground.
------Oh, I'm very sorry. I ____ the dustbin there.
| A．don't see | B．isn't seeing | C．didn't see | D．haven't seen |
You will be successful in the interview __________ you have confidence.
| A．before | B．once | C．until | D．though |
—Where’s that report?—I brought it to you __________ you were in Mr. Black’s office yesterday.
| A．if | B．when | C．because | D．before |
The field research will take Joan and Paul about five months; it will be a long time __________ we meet them again.
| A．after | B．before | C．since | D．when |
It has been announced that candidates(应考者) ________ remain in their seats until all the papers have been collected.
| A．can | B．will |
| C．may | D．shall |
I ________ pay Tracy a visit, but I am not sure whether I will have time this Sunday.
| A．should | B．might |
| C．would | D．could |