The Grade 9 students often have a picnic Sunday afternoons.A. inB. onC. atD. to

问题补充：

The Grade 9 students often have a picnic Sunday afternoons.

A. in

B. on

C. at

D. to

答案：

A. in

(答案→)B. on

C. at

D. to

解析：此题考查介词的用法。在星期日的下午要用介词on。