___,everything would have been all right.A.he had been here B.here he had been C.ebbn herehe had

这道题考的是虚拟语气的倒装.
根据题干would have been可知是对过去的虚拟,if 从句中用had done 可以表示对过去的虚拟.
if 引导的虚拟语气,可以将if 省略掉,将had/were/should提至主语之前.
这道题的正常语序:If he had been here.
倒装语序：Had he been here.
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