问题补充：
--- Was Tom a member of Greener China?
---Yes, he has Greener China for 5 years.
A. taken in
B. joined
C. been in
D. been to
答案：
A. taken in
B. joined
(答案→)C. been in
D. been to
解析：
试题分析: 句意：汤姆是中国环保的一个成员吗？是的，他已经在中国环保5年了。join加入，瞬间动词，延续性动词为be in; 根据for 5 years.五年了，可知选C
