楼主,look after表照顾,如：He looked after his sister look up 一般指在字典里查找单词什么的,look up the word in the dictionary.look for 指寻找,更倾向于找的过程,动作,（顺便提一下） find也是寻找,但更倾向于结果.I looked (look的过去式）for my shoes ,but I couldn't find them .look over 多指检查,考试检查之类的 Please look over your exam paper carefully.