I can still remember that it is since the 1990’s, _____ we began to use cell phones,_______ the number of mobile users has greatly increased．
#79738
A
while; when
B
when; what
C
before; that
D
when; that
推荐题目
___ has already been pointed out is that grammar is not a set of dead rules.
#30960
A
As
B
It
C
What
D
Which
I cannot hear the professor clearly as there is too much noise ________ I am sitting.
#31189
A
before
B
until
C
unless
D
where
The traditional view is ________ we sleep because our brain is “programmed” to make us do so.
#29975
A
when
B
why
C
whether
D
that
I'm sorry you've been waiting so long，but it'll still be some time ________ Brian gets back.
#30681
A
before
B
since
C
till
D
after
You can go out, _________you promise to be back before 11 o'clock.
#31525
A
as far as
B
so far as
C
when
D
as long as