问题补充：
The skirt she spent 50 yuan is very beautiful on her.
A. in which
B. on which
C. for which
D. which
答案：
A. in which
(答案→)B. on which
C. for which
D. which
解析：考查定语从句。本题的先行词是the skirt，定语从句中缺少on the skirt，用介词on +which引导定语从句，句意：她花了50块钱买的裙子穿在她身上很好看。故B正确。
