Question

【题目】She _________the sign language before she served as a volunteer to help the deaf.

A. learns B. has learned

C. was learning D. had learned

Answer 1

【答案】D

【解析】试题分析：句意：她作为一名志愿者来帮助聋人之前已经学习了手语。由句意可知，学习手语在做一名志愿者之前，是过去的过去，用过去完成时，故选D。

考点: 考查动词时态的用法。