5. In our class, when the bell rang and the taacher closed his book, it was a or everyone to stand up.
| A．signal | B．chance | C．mark | D．measure |
．Never before______ so highly successful in his attempts to forecast the weather accurately on a small scale．
| A．man has been | B．man is | C．has man been | D．will be man |
．__________, we would not have achieved so much.
| A．If they didn’t help us | B．If it hadn’t been their help |
| C．Weren’t it for their help | D．Had it not been for their help |
How long___ stay with the company depends on___we’re satisfied with each other.
| A．I will; if | B．I will; whether |
| C．will I; if | D．will I; whether |
No．50 High School is as new as No．48 High School．____, it is more beautiful．
| A．If anything | B．If something | C．If necessary | D．If so |
．It will be about three years________next Olympic Games are held.
| A．when | B．since | C．that | D．before |