问题补充:
The country life he was used togreatly since the opening policy.
A. changed
B. has changed
C. changing
D. having changed
答案:
A. changed
(答案→)B. has changed
C. changing
D. having changed
解析:此题考查考生对句子结构的分析理解能力。此题中he was used to为定语从句,对the country life进行修饰,所要选的内容应为句子的谓语动词,故排除C、D,而since通常用于现在完成时态。故选答案为B。