wo must do sth to protcet the tigers改被动语态如题

wo must do sth to protcet the tigers改被动语态如题 must do sth 还是 must to do sth must 后面是加to do sth.还是do sth. 请问must to do sth?句型对吗? 能用must have to do sth 吗? Attentions must be paid to do sth还是doing sth 是must doing sth 还是to do sth? must to do sth 和 have to do sth和need to 的用法急 must 后面是加do sth.还是 to do sth.有没有人呐、 must do sth must not do sth 造句 各三个 must do sth must not do sth 造句 各三个 Sb must do sth造句 It's a must to do sth.must在这里是什么词?意思是什么? do sth to do 英语句式：must do/to do sth?谁知道有别的句式也请说一说.. It must be taken actions to do sth.和 Actions must be taken to do sth.的区别这两个意思是不是一样的？ have sth to do need sth to do