“介詞＋關(guān)系代詞”,無非就是代替先行詞的關(guān)系代詞在從句中擔(dān)任"介詞賓語".正確使用就要了解這個(gè)介詞是根據(jù)什么來定的.
　　1.　介詞是跟動(dòng)詞搭配,動(dòng)詞往往不及物,或動(dòng)詞短語帶有介詞.
　　　　I visited the city in which my father had worked for 10 years.(work in the city)
　　　This is a very important problem to which we all should pay attention.(pay attention to the problem)
這種情況一定要注意短語動(dòng)詞　look for,run into 之類的,整個(gè)視為一個(gè)單詞,在句中不能拆開使用.
This is a problem most of us are likely to run into.
It is the right book that she was looking for.
2.介詞跟形容詞搭配使用.
Every student should do the assigned tasks for which they are responsible independently.(be responsible for)
3.介詞跟在名詞后面
He had a wonderful chilhood,about which he wrote many stories.(stories about )
4.狀語是一個(gè)介詞短語
The professor wrote for him a letter of recommendation with which he applied for a position in that company.