问题补充：
–Kate, do you know it is from here to the gym?
–About twenty minutes’ walk.
A. how long
B. how far
C. how soon
D. how often
答案：
A. how long
(答案→)B. how far
C. how soon
D. how often
解析：句意：——凯特，你知道从这儿到体育馆有多远吗？——大约步行20分钟。A. how long多长时间，B. how far多远， C. how soon 多久，D. how often多长时间一次。结合句意表示距离多远，故选B.
