1.Don't you think it is time you_____smoking?
A give up B gave up C would give up D should give up
答案是B 这个句型不是应该是it's time that you (should) +动词原形吗
2.___was pointed above, this substance can be used as a substitute.
A.It B That C What D AS
答案是D That 为什么不可以用
3. If i say i don't think much of this book,this means that___.
A.I never read it B .I seldom think about it
C.I have no idea of it D.I have a poor opinion of it
答案是D B我觉得也符合题意啊～～