Is this tourist attraction you paid a visit to several days ago?
#30600
A
that
B
which
C
the one
D
where
推荐题目
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