是must to do还是must doing 还是must do?
是must to do还是must doing 还是must do?
must doing还是must to do?
是must be to do还是must be doing
must 是跟do 还是doing
是must doing sth 还是to do sth?
must not 后面加do doing 还是to do?
must 的用法是must sb do 还是must sb to do
Attentions must be paid to do sth还是doing sth
must do sth 还是 must to do sth
must 后面是加to do sth.还是do sth.
must 后面是加do sth.还是 to do sth.
have to 和must 的区别是什么记住,一定要直观,比如是 I must还是have to do my homew