16.He found it hard to concentrate on his writing ______ so many people around.

A.when

B.during

C.because

D.with

17.When she was five,the girl’s father decided to ______ a pianist of her.

A.develop

B.build

C.make

D.do

18.______ automobile pollution,the air quality in this city has become worse.

A.As a result of

B.In spite of

C.But for

D.As for

19.Her friends did not expect her to ______ all their suggestions.

A.turn down

B.turn over

C.take off D.take away

20.The motor isn’t ______ enough to push the car up the hill.

A.tough

B.powerful

C.strong

D.big