主词+动词+as if/as though+主词+were/   had+pp
 
He talks as if he were a doctor.他的谈吐好像他是个医生.....事实上 ,他不是医生
*as if 或as though都表示 "好像是"
as if+主词+were  表示与现在事实相反
as if+主词+had+pp  表示与过去事实相反

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