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He has behaved in the most extraordinary way recently, I wonder what can _______his actions.          
| A.answer for | B.wish for | C.ask for | D.account for | 
There is a possibility that these hens could be frightened and lay fewer eggs a sudden loud noise.
| A.should there be | B.there was | 
| C.would there be | D.there having been | 
—I’m going to the post office.
 —you’re there, can you buy me some stamps?
| A.Because | B.While | C.As | D.If | 
—How long in America?
 —Two years. I came back last month.
| A.have you studied | B.do you study | 
| C.would you study | D.did you study | 
What will we do when all the oil in the world has ?
| A.run out of | B.been given out | C.been used up | D.given off | 
She was a person and wouldn’t let anyone or anything stop her.
| A.reliable | B.determined | C.stubborn | D.concerned |