look over（察看, 检查）  vs  overlook  （漏看，忽略） (来源：英语电影下载 http://bt.englishcn.com)

Look over is a phrasal verb.

When you look over something or someone you quickly examine it or them. (来源：英语聊天室 http://chat.EnglishCN.com)

For example:-

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I asked my teacher to look over what I had written.

Overlook is a verb. (来源：EnglishCN英语博客基地)

When you overlook someone or something you fail to notice or consider it or them.:

For example:

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I think my teacher overlooked some of my mistakes.

!Look over is two separate words, overlook is one word.
 

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