主詞+動詞+as if/as though+主詞+were/   had+pp
 
He talks as if he were a doctor.他的談吐好像他是個醫生.....事實上 ,他不是醫生
*as if 或as though都表示 "好像是"
as if+主詞+were  表示與現在事實相反
as if+主詞+had+pp  表示與過去事實相反

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