1.a an
2.aboard和by
3.abound in和rich in 以及abound with和rich with
4.about
5.about和on
6.about to 和not about to
7.above+名词、代词或动名词
8.above和over
9.be not above
10.accomplish,complete和finish
11.in accord with和in accordance with
12.according as+从句
13.according to+名词和in someone’s opinion
14.account for
15.accuse someone of和charge someone with
16.acquaint someone with 和 be acquainted with
17.across,over 和 throught
18.actually,in fact,as a matter of fact 和to tell the truth
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