the guidance of my teacher 1 won the first prize in the English Speech Contest.A. WithB.

问题补充：

the guidance of my teacher,1 won the first prize in the English Speech Contest.

A. With

B. After

C. Under

D. In

答案：

A. With

B. After

(答案→)C. Under

D. In

解析：

试题分析:考查介词辨析。A和。。。一起；B在。。。之后；C在。。。下；D在。。。里。固定短语 under the guidance of sb或者under one’s guidance“在。。。的指导下”，所以C选项正确。句意：在老师的指导下，我获得了英语演讲比赛的一等奖。