16 My teacher always helped me __D__ when I had trouble with my English   study.

A with B off

C away D out

17 If you have met with difficulty， please don't __A___ to let know.

A hesitate B trouble

C stop D bother

18 I _B____ us more achievements in the coming new year.

A hope B wish

C expect D predict

19 In this factory all the workers are paid ___B__.

A by hours

B by the hour

C by an hour

D by hour

20 They designed a flat building which could ___A__ two thousand   families.

A hold B space

C house D live