My parents will work the farm the morning of June 15.A. in inB. on onC. in onD. on i

问题补充：

My parents will work the farm the morning of June 15.

A. in, in

B. on, on

C. in, on

D. on, in

答案：

A. in, in

(答案→)B. on, on

C. in, on

D. on, in

解析：句意：我的父母将在6月15日的早晨在农场上班。这里是短语on the farm在农场；在具体的某一天应该用介词on。故选B。

考点: 考查介词的用法。