___ volleyball is her main focus, she is also good at tennis.
| A．Since |
| B．Once |
| C．Unless |
| D．While |
--What made her so upset?
-- __________
| A．Lost her bike. | B．Losing her bike, |
| C．She lost her bike . | D．Because of losing her bike. |
—Sorry, Mr. Wang. I didn’t finish the assignment yesterday.
Oh, you ________ have done it as yesterday was the deadline.
| A．must | B．mustn’t | C．should | D．shouldn’t |
—How long do you think it will be___ the Stock Market returns to normal?
—At least one year, I guess.
| A．before | B．when | C．until | D．that |
His promise ___ he would marry her when he came back turned out to be a lie, ___ left the girl heart-broken.
| A．which; what | B．that; which | C．what; which | D．which ; that |
If we ___________some measures, we might have prevented the environmental pollution．
| A．take | B．had taken | C．took | D．have taken |