问题补充：
Great changes __ in the city in the past 20 years, and a lot of factories .
A. have been taken place; have been set up
B. have taken place; have set up
C. have taken place; have been set up
D. were taken place; were set up
答案：
A. have been taken place; have been set up
B. have taken place; have set up
(答案→)C. have taken place; have been set up
D. were taken place; were set up
解析：此题重点考查take place和set up两个短语的用法。前者表示发生，没有被动语态。Set up表示搭建有被动语态。
