I usually stay bed Sunday morning. A. at; inB. in; onC. on; onD. for; on

问题补充：

I usually stay bed Sunday morning.

A. at; in

B. in; on

C. on; on

D. for; on

答案：

A. at; in

(答案→)B. in; on

C. on; on

D. for; on

解析：句意:我星期天的早上通常呆在床上睡懒觉。stay in bed 呆在床上睡懒觉，是一个固定短语；Sunday morning 指的是具体一天的早上，故应该用介词on。故选B。