look up的意思是：向上看；改善;拜访（某人）；查找。
例句:
1、He looked up from his newspaper(他停止看报纸，把头抬了起来。)
从…上抬头看
例句:
2、Things are looking up for us(事情正在朝着对我们有利的方向发展。)
例句:
3、If you don't know a word，look it up in the dictionary(你要是不认识某个单词就查查词典。)
例句：
4、I looked the company up on the Internet(我在因特网上找到了这家公司。)