Betty usually gets up six every morning. A. inB. onC. toD. at

问题补充：

Betty usually gets up six every morning.

A. in

B. on

C. to

D. at

答案：

A. in

B. on

C. to

(答案→)D. at

解析：句意：贝蒂通常在每天早晨六点钟起床。at和时间点连用，in用于一段时间前，on 用于具体的一天，根据句意，故选D。