--- is it from your school to the park?
--- 30 minutes’ walk, I think.
A. How long
B. How far
C. How soon
D. How often
网友回答
A. How long
(答案→)B. How far
C. How soon
D. How often
解析：how long 问的是多久，要用for +一段时间来回答，而how soon用来提问未来多久的意思，要用in +一段时间来回答，而how often 表示多久一次，用次数+时间来回答，而答语内容为30 minutes’ walk，可知问语为how far，故选答案为B