Mr Ren always went to work (on foot) last year.对括号里的提问
问题描述：
Mr Ren always went to work (on foot) last year.对括号里的提问
( )Mr Gao ( ) to work last year?
回答的格式
答
How did Mr Ren go to work last year?
on foot 是指Mr Ren去上班的方式（交通工具）,对交通工具提问要用how
这句话表示的是去年的事,所以是过去式要用did