首先should have done是表示该做的事却没做,表示对过去没做的事表示遗憾.shouldn't have done所表示的意思相反.
could do和may climb是情态动词中便是现在,如果要表示过去则必须用have done表过去.as all the other windows and doors were closed注意到是“were”说明表示的过去.
must have done表示对过去的判断和推测的肯定语气.
首先should have done是表示该做的事却没做,表示对过去没做的事表示遗憾.shouldn't have done所表示的意思相反.
could do和may climb是情态动词中便是现在,如果要表示过去则必须用have done表过去.as all the other windows and doors were closed注意到是“were”说明表示的过去.
must have done表示对过去的判断和推测的肯定语气.