___in the air, this kind of steel become harder and harder.A．CoolingB．Having coo

题型：不详难度：来源：

___in the air, this kind of steel become harder and harder.

A．Cooling

B．Having cooled

C．Being cooled

D．Cooled

答案

解析

略

举一反三

Hearing his words, I couldn"t decide ______ or remain.

A．whether to go abroad	B．if I go abroad
C．if to go abroad	D．to go abroad

题型：不详难度：| 查看答案

___________his homework, the boy went out to play.

A．Doing

B．Done

C．Having done

D．To do

题型：不详难度：| 查看答案

The teacher doesn’t permit ___________in class.

A．smoke

B．to smoke

C．smoking

D．to have a smoke .

题型：不详难度：| 查看答案

______to use in April,2005,the road has solved the long-standing problem of traffic jams of this area．

A．Put

B．Putting

C．Having put

D．Being put

题型：不详难度：| 查看答案

A number of people have posted their own videos on the website You Tube, ____________their attempts to become “musicians”.

A．to show

B．showing

C．showed

D．show

题型：不详难度：| 查看答案