—Have you known Dr. Jackson for a long time?—Yes since she the Chinese Society.A. has j

问题补充：

—Have you known Dr. Jackson for a long time?

—Yes, since she the Chinese Society.

A. has joined

B. joins

C. had joined

D. joined

答案：

A. has joined

B. joins

C. had joined

(答案→)D. joined

解析：.

D。since she join the Chinese Society为I have known Dr. Jackson since she join the Chinese Society之省略。连词since所搭配的时态通常是：主句用现在完成时，从句用一般过去时。