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
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You have failed two tests. You’d better start working harder, ____ you won’t pass the course.
#30694
A
and
B
so
C
but
D
or
I can’t find a proper dictionary _______ I can turn in my study.
#33890
A
to which
B
up which
C
on which
D
for which
One advantage of playing the guitar is it can give you a great deal of pleasure.
#33798
A
how
B
why
C
when
D
that