Unit 5 Safety 安全
Don't run down the stairs. 别跑下楼梯。
It's dangerous! 很危险!
Don't climb on the window ledge. 别爬窗台。
Be careful! 小心点!
Use the sidewalk. 走人行道。
OK! 好!
Please wait for the green light. 等到绿灯再走。
It's safe. 很安全。