Question

you should consider the effect that have on you

Before you left your position，you should consider the effect ________ will have on you．（　　）

A. it

B. one

C. which

D. that

Answer 1

答案：A．本题句子主干为：you should consider the effect ________ will have on you．而________ will have on you为定语从句，修饰先行词the effect．
很明显，该定语从句的关系代词代替先行词the effect，在从句中充当have的宾语，所以关系代词可以省略．但是，该定语从句还缺少一个主语：__ will have on you，所以必须使用代词it充当该成分，它指的就是前面的you left your position．故选A．