Lucy often gets up9:00Sunday morning.A. at, on B. at, in C. in, on D. in, in

Lucy often gets up 9:00 Sunday morning.
A. at, on
B. at, in
C. in, on
D. in, in

(答案→)A. at, on B. at, in C. in, on D. in, in解析：在表示时间时,in表示在一个时间范围;at表示在具体时刻;on表示在具体某一天.本句中九点为具体时刻,故用介词at.星期日上午为具体某一天,故用介词on,选A.

我明天再问问老师，叫他解释下这个问题