【题目】—I wonder what makes him a good English teacher.
—He ________ as a volunteer in the UK for three years, which helps with his work a lot.
A. served B. has served C. serves D. had served
在线课程【答案】A
【解析】考查动词时态。句意：——我想知道是什么使他成为一个好的英语老师。——他在英国做了三年志愿者，这对他的工作帮助很大。此处是叙述过去发生的事，用一般过去时即可，故选A。