I usually do my homework after dinner until 10 pm is my bedtime.A. whoB. whatC. whichD.

问题补充：

I usually do my homework after dinner until 10 pm, is my bedtime.

A. who

B. what

C. which

D. that

答案：

A. who

B. what

(答案→)C. which

D. that

解析：考查非限制性定语从句，先行词是10 pm,而定语从句中缺少主语，用关系代词，因为非限制性定语从句不能用that，所以用which引导定语从句，句意：我通常晚饭后做作业到晚上10点，这是我的睡觉时间。选C。