【题目】A new subway ________ in Changsha and it will be open to traffic when completed next year.
A. has built B. has been built
C. is building D. is being built
在线课程【答案】D
【解析】
试题分析：考查时态与语态。根据下文的it will be open to traffic可知，这条高速公路还没有建成，故答案在C、D中产生。再根据主语为高速公路可知，和动词之间存在被动关系，故选择D。