问题补充：
-— How far apart do they live?
---- I know，they live in the same neighbourhood．
A. As long as
B. As well as
C. As far as
D. As often as
答案：
A. As long as
B. As well as
(答案→)C. As far as
D. As often as
解析：本题考查词组辨析。As far as I know具我所知，其它含义不对，故选C。
