很高兴为你解答.
保证正确率~!
正确答案是：
1、No one is 【allowed 】to 【 break 】the school rules
2、 Could you please be more 【polite 】 to the old people?
3.、 It's【impolite】to shout at people .
4、It's impolite 【to laugh】at people who are in trouble.
5、 We students should try【not to cut】 in line while we are waiting for the bus.
6.、You'd better 【not talk】in class.
7、You are not 【allowed】 to smoke here.
8、Mom doesn't allow me【to play】 computer games on weekdays
祝开心~!