—You seem to have known Dr. Ken for a long time.
—That’s true. he joined our club years ago.
A. Since
B. Until
C. When
D. If
网友回答
(答案→)A. Since
B. Until
C. When
D. If
解析：连词辨析。A. 自从……以来 B.直到 C. 既然，当……时 D. 是否，如果。句意：你好像认识肯博士很久了。——是的，自从他几年前加入我们俱乐部以来。故选A。