as分两种情况，进行时和一般时。as：prep.像;如同;作为;当作。adv.(比较时用)像…一样，如同;(指事情以同样的方式发生)和…一样。conj.当…时;随着;照…方式;因为;由于。

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She used her family's history as a base for her novel.

她以她的家族史作为小说的素材。

My new job is much the same as the old one.

我的新工作和旧工作差不多。

Take as much time as you like.

你想花多少时间就花多少时间。

Research will be needed as a preliminary to taking a decision.

作出决定之前需要进行研究。

This year's results are virtually the same as last year's.

今年的.结果几乎和去年的一样。