不能用must be done的形式.因为must have done强调的是动作已经完成.
can't和couldn't是可以通用的,但是后者的语气较委婉.
must＋have done 句型
1个回答
相关问题
-
must have been done must have done
-
must have been done/must be done
-
must be done和 must have done区别
-
should have done;must have done;need have done;could have do
-
情态动词+have done 如 could have done,must have done,should have
-
must be must have done 区别
-
MUST have been done
-
could/should/must/.加have done和have been done区别
-
must have done 和 should have done 的表示推测区别?
-
must have done 表示猜测 那 must do 表示什么