用should或shouldn’t填空。 1.You _________ drink too much water before running. 2.You _________ leave school during the school hours. 3.You _________ cross the road when the traffic light is green. 4.You _________ tell your teacher if you see a classmate in trouble. 5.You _________ run in the library. 6.You _________ swim in the river. 7.You _________ be careful when you cross the street. 8.You _________ walk on the wet floor.