1. If sb had done sth (坏事), sb would never have done sth (好事). 如果某人过去做了某事(坏事),那么他永远不可能做某事。 If Hugh Miller, after toiling all day in quarry (采石场), had devoted his evenings to rest and recreation, he would never have be...
You shouldn't have been so rude to him. 你本不应该对他那么粗鲁。 注:“should have + 完成式”虽然可以表猜测,但因为会造成歧义,应少用。 ought to have done 1、“ought to have + 动词的完成式”表示过去应做某事而实际未做,它的否定形式表示本不应该做某事却做...
比较have to和must 1) 两词都是"必须"的意思,have to表示客观的需要,must 表示说话人主观上的看法,既主观上的必要。 My brother was very ill, so I had to call the doctor in the middle of the night.我弟弟病得很厉害,我只得半夜里把医生请来。(客观上需要做这件...
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