题目内容：

it is a great pity that susan has to leave .how nice it if she a bit longer.A.would be stayed B.is can stay C.should be stays D.was is able to stay 为什么选A

优质解答

这是虚拟语气.她不能呆更长的时间,只是希望她能多呆一段日子.虚拟语气主句用过去将来时,从句用一般过去时.would be是过去将来时,stayed是一般过去时.