连词有：as, as if/ as though

(1) as引导的方式状语从句, 意为"以……方式;如同……那样"，从句有时是省略句。如：

Do as I say. 要照我说的做。

I did just as you told me. 我正是照你说的办的。

Air is to man as water is to fish. 空气之于人犹如水之于鱼。

(2) as if/as though引导的方式状语从句

as if和as though的用法相同，都作"好像，仿佛"解。如：

二者引导的状语从句往往用虚拟语气，表示与事实相反。as if比as though更为常用。但也可用陈述语气，表示所说的情况是事实或实现的可能性较大。如：

They looked at me as if , as though I were mad.

他们瞧着我好像我发疯了似的。

They look as if/as though they know each other.

他们看来好像互相认识。

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