【题目】根据所学内容填空。
1. Do cross the street ______the traffic lights or safety crossing.
2. Don’t _____on the stairs.
3. Do ______at the traffic lights or safety crossing.
4. Don’t _____ tall trees.
5. Don’t run ______the stairs.
【答案】1. at 2.run 3. cross the street 4. climb 5. on
【解析】
略
