For some time the expert __________ people of the health risks caused by passive smoking. He says he won’t stop until all the smokers around him decide to quit smoking.
| A．is warned | B．is warning | C．has been warning | D．has been warned |
Don’t forget _____ the book to the library when you finish _____ it.
| A．to give back ; to read | B．to return ; reading |
| C．returning ; reading | D．returning ; to read |
Marry was so excited _____ she received an invitation from her friend to visit Beijing.
| A．where | B．that | C．why | D．when |
——When did the plane_____ ?
——Well, it left two or three minutes ago.
A. take up B take away C take off D take out
—— Can’t you notice the person shaking hands with the leader? He is our classmate Tom!
—— Oh, my God ! I ____________ him.
| A．don’t recognize | B．didn’t know | C．don’t know | D．didn’t recognize |
Though tigers are ______ to people, they are ______ now and we should protect them or they will die out.
| A．dangerous ; dangerous | B．in danger ; in danger |
| C．dangerous ; in danger | D．in danger ; dangerous |