Itisprettywellunderstoodcontro

It is pretty well understood ________ controls the flow of carbon dioxide in and out the atmosphere today.

A．that

B．when

C．what

D．how

登录免费查看答案和解析

相关试题

At the beginning of class, the noise of desks ______ could be heard outside the classroom.

A．opened and closed	B．to be opened and closed
C．being opened and closed	D．to open and close

收藏答案/解析

Yesterday morning he got up earlier than ______, for it was not a(n) ______ day.

A．common; usual

B．common; ordinary

C．usual; normal

D．usual; ordinary

收藏答案/解析

The medical reform in that country turns out to be ______ failure, but as we know, success often comes after ______ failure.

A．a; the

B．a; 不填

C．a; a

D．不填; 不填

收藏答案/解析

Having a trip abroad is certainly good for the old couple, but it remains ______ whether they will enjoy it.

A．to see

B．to be seen

C．seeing

D．seen

收藏答案/解析

It was raining heavily. Little Mary felt cold, so she stood ______ to her mother.

A．close

B．closely

C．closed

D．closing

收藏答案/解析