问题

They have not made any decision on ______they are going to do to deal with the waste and control pollution.

A:that
B:which
C:if
D:what

正确答案是：

同类题型

Did you know China is one of the oldest countries in the world—Yes, I did. It’s ________ than the US.

Mary went to the box office at lunch time, but all the tickets ____ out. [ ]

My pen pal said he would write to me, but I _____ any letters from him so far.

Is it only when you fail _________ you will be awareof your mistakes

, which used to be called“love-apple”, is not ____but ______