1、（ ）he was at home,Iwould have phoned him then

题目

1、（ ）he was at home,Iwould have phoned him then
A.Had I known B.I had konwn C.Would I known D.I would know
2、we have been doing a lot of gardening( )
A.late B.latest C.latter D.lately
3、竖直上抛一质量为m的小球,经t秒小球重新回到抛出点,若取向上为正方向,那么从抛出到重新回到抛出点的过程中,小球动量变化量为（ ）
A.-mgt B.mgt C.0 D.-mgt/2

答案

1.A 这是一个倒装而且也是个省略句.补充完整是：If I had known.省略If 则倒装为A.这是一个与过去试试相反的虚拟语气.从句用过去完成时had done 的形式,主句用would have done2.选D表示最近,近来,A是迟到的意思.B是...