Ⅰ. look “看”指看的意识，强调看的行为动作。是不及物动词。不能直接接宾语。如：
① Look, they are playing on the playground.
Ⅱ. look for “寻找”指有目的地找。强调“寻找”这一动作。
① What are you looking for? 你在找什么?
Ⅲ. find “找到、发现”指经过一番努力后“找到”丢失的人或东西。强调“找”的结果。如：
① I can’t find my pen. 我找不到我的钢笔了。
② The poor granny is looking for her little son. I hope she can find him. 这个可怜的老奶奶在找她的小儿子，我希望她能找到他。
Ⅳ. find out “找出、查明”用着及物动词短语，常表达找出答案，弄明真相，查明情况等意思。如：
① Please find out when the train leaves. 请查一下火车什么时候离站。
Ⅴ. look up “向上看;查字典”如：
① She looked up and she saw many birds in the sky.
② You must look up the new words when you don’t know how to pronounce it.