---How long have you known the doctor ?  ---_________he helped me three years ago.
#56019
A
When 
B
Before 
C
Because
D
Since
推荐题目
Mary _____ go to bed ______ her mother came back last night.
#56886
A
not, until
B
doesn’t , until
C
aren’t, until
D
didn’t, until
______I know him, ______I hardly talk to him.
#58081
A
Although; but
B
Although; /
C
/; Although
D
But; although