My sister has to study her Chinese test Tuesday morning.A. at onB. on forC. for inD.

问题补充：

My sister has to study her Chinese test Tuesday morning.

A. at, on

B. on, for

C. for, in

D. for, on

答案：

A. at, on

B. on, for

C. for, in

(答案→)D. for, on

解析：D “为......而学习”是study ...for...，具体的某一天（的上下午晚上）用介词on。