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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－Did Tom go back late last night?—No. It was just nine o’clock he arrived home.
#32970
A
when
B
after
C
until
D
that
Just use this room for the time being, and we'll offer you a larger one ________ it becomes available.(2010·安徽)
#29961
A
as soon as
B
unless
C
as far as
D
until
How can they expect to learn anything ________ they never listen?
#30286
A
whether
B
when
C
but
D
unless
Leave your key with your neighbor _you lock yourself out one day.
#31885
A
as long as
B
in case
C
even though
D
as if