as 引导的短语可以做宾语补足语,as 还可以引导定语、状语从句。如:
He describes himself as a doctor. 他自称是医生。(作宾补)
As is well-known, Taiwan belongs to China. 众所周知,台湾是中国的一部分。(as引导定语从句)
As he is ill, he cant' come to school. 因为他病了,所以他不能来上学。(as 引导原因状语从句)
As he was walking alone the street, he saw a girl begging on the sidewalk. 当他沿着大街走的时候,看到一个姑娘在人行道上乞讨。(时间状语从句)
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