Highfield School rules
Students must：	Students must not：
1． wear their school uniforms every day．	5． eat or drink in the classroom．
2． arrive at the school on time．	6． run in the building．
3． listen to the teacher carefully．	7．draw pictures on their desks．
4． keep the school clean．	8． talk to each other in class．

书面表达：根据上面的提示， 写一篇小短文，描述 Highfield School的校规．
温馨提示：1． 对于规则中要求必须做到的事项用must来叙述；
2． 对于那些绝对不允许出现的现象用mustn't来叙述．