As if, like, As though

As if and As though (meaning a situation seems to be) are the same in meanings. Americans use "like" in informal English as the substitute of As if or As though but many experts regard it as incorrect in formal English.

Following are some examples:

1.  He treats her like he was her husband__a better structure would be he treats her, as if, he was her husband.
2. He sat in a manner, as if, he was the president.
3. It looked, as if, they were trying to conceal the truth. 

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