问题补充：
. Dr. Smith, together with his wife, visit Beijing this summer.
A. is going to
B. are going to
C. was going to
D. were going to
答案：
(答案→)A. is going to
B. are going to
C. was going to
D. were going to
解析：本题的含义是史密斯医生和他的妻子今年夏天打算到北京去，表示计划可用be going to，本题主语的关键词是史密斯医生，为单数，故用is，故本题选A。
