---How long have you known the doctor ?  ---_________he helped me three years ago.
#56019
A
When 
B
Before 
C
Because
D
Since
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I won’t pass the exam ______I work hard.
#58063
A
whenever
B
because
C
if
D
unless
The camera is too expensive ________.
#56131
A
for him to buy it
B
so that he couldn’t buy it
C
so that he can’t buy
D
for him to buy