改写英语句子.

题目

改写英语句子.
The boy walk about in order to keep warm .（改为同义句）
There used to be low and dirty houses.(改为反义疑问句）
Parents should allow teenagers to choose their own clothes .（改为含情态动词的被动语态）
I don not know which mobil phone I should choose.（改为简单句）
In 1519 a traveler went to American from Europe .He discovered the tomato .（合并为含定语从句的复合句）
I have been to Hong Kong _____ _____ _____ on the left.（同上）
保护环境是我们每个人的责任.It is _____ _____ ____ _____ the environment.
今天我离开家的时候卫生间的灯亮着.Tihs morning I left home ____ ____ ____ ____ ____.

答案