为什么claim to have done可以,而say to have done不可以?
have done/to be done
should have done 可以换成 ought to have done嘛?
claim to have done sth 是声称做过某事 可是to do 和 to have done 有什么区别?
have done to
to have done
meant to have done
to have done , having done 选哪个?为什么?
done,tobe done,to have been done,to have done,having done,ha
have been done 和 to be done
were to have done 造句,
the 序数词 to have done
不定式 to have done 举例