问题补充：
His grandfather and grandmother Chongqing for 40 years. They like living there.
A. have been in
B. have been to
C. have gone to
D. have moved to
答案：
(答案→)A. have been in
B. have been to
C. have gone to
D. have moved to
解析：本题意思是他的爷爷奶奶已经在重庆呆了四十年，谓语动词应是持续性动词，从时间状语来看，本题为现在完成时态，所以选A。
