根据中文提示补全句子。
【小题1】Don’t run on the ______ (楼梯).
【小题2】Look, the boy is crossing the road at the ______ ______ (安全十字路口).
【小题3】The girl gets sick, because she ______ (吃) a bad apple last night.
【小题4】Students should know how to ______ ______ (保持安全).
【小题5】You can call “110” when you are ______ ______ (遇到麻烦).