look的用法：
用作不及物動詞，意為“看，望，瞧”。
1、單獨使用時，后不跟介詞。如：
I looked but saw nothing.我看了，但什么也沒看見。
Look！ Here comes the bus.瞧！汽車來了。
Look before you leap.三思而后行。
2、和at連用。如：
The teacher is looking seriously at us.老師正嚴肅地看著我們。
Look at these pictures. How beautiful they are！看這些畫，它們是多么漂亮啊！
3、和其它某些介詞或副詞連用：
（1）look after 照看，照料。如：He is old enough to look after himself.他年齡足夠大，能照看自己。
（2）look for 尋找。如：I looked for you just now， but I didn’t find you.剛才我到處找你，但沒有找到。
（3）look around 四下環顧;到處尋找。如：He looked around but he saw nobody.他四下環顧，但什么人也沒看到。
（4）look back on回想，回顧。如：They often look back on the days they spent together.他們常回顧他們在一起度過的日子。
（5）look down on看不起。