2.Look at that sign.Smoking__here.

问题描述:

2.Look at that sign.Smoking__here.
A.isn't allowed B.doesn't allow C.aren't allowed D.don't allow解释并翻译

选A
句意:看那个告示牌,这儿禁止吸烟.
词句为被动语态,结构为be+not+动词过去分词
that sign是单数,所以be动词选is
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