The rescue team made every __________ to find the missing mountain climber.
| A．force | B．energy | C．effort | D．possibility |
Teenagers ________ their health because they play computer games too much．
| A．have damaged | B．are damaging |
| C．damaged | D．will damage |
Peter’ shirt looked just the same as Tom’s，but it cost ______ his．
| A．as much twice as | B．twice as much as |
| C．much as twice as | D．as twice much as |
We can’t figure out ______ quite a number of insects and birds are dying out．
| A．that | B．as | C．why | D．when |
______ environmental damage is done，it takes many years for the ecosystem to recover．
| A．Even if | B．If only |
| C．As if | D．Once |
If Susan ______ for ten more minutes at the party last night, she might have met Johnny Depp, the famous Hollywood star．
| A．stayed | B．would stay |
| C．had stayed | D．would have stayed |