The new system needs to be in operation for five months ________ it can be updated.
#30274
A
as
B
while
C
before
D
once
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So although Fleming discovered penicillin, it was over a decade ___________someone else turned penicillin into the great drug of the 20th century.
#34272
A
when
B
that
C
before
D
unless
I would appreciate it you call back this afternoon for the doctor’s appointment.
#31617
A
until
B
if
C
when
D
that