问题补充：
Lucy fell asleep she was listening to music.
A. before
B. while
C. after
D. as soon as
答案：
A. before
(答案→)B. while
C. after
D. as soon as
解析：词义辨析。Before在……之前；while当……时候；after在……之后；as soon as一……就。根据she was listening to music用的是过去进行时，所以选B。露西听音乐时想睡觉。
