Life is very important and precious for everybody.There is one thing that we should pay attention.Our school life could be dangerous if we are not careful enough.For example,one day,two students ran after each other in the hallway.Suddenly,one of them fell down and hurt his leg because of the wet floor.Therefore,he had to stay in the hospital for several days.So I think students should walk and do not run in the hallways.And the teachers had better keep one eye on the students after class and stop them from running.At last ,I hope all the students should pay attention to their safety in school.