(2013·潍坊高考模拟)Air pollution is getting more and more serious，so we must take action________it is too late.
#30055
A
before
B
after
C
until
D
when
推荐题目
_______ the calculation is right, scientists can never be sure that they have included all variables and modeled them accurately.
#79673
A
Even if
B
As far as
C
If only
D
So long as
—I wonder whether the speaker has arrived.— ________ ，I’ll check at the reception desk.
#32400
A
Wait and see
B
Beg your pardon
C
If you’ll excuse me
D
It’s still early
I’m sorry I got caught in the traffic；_________, I could have been here sooner．
#33598
A
besides
B
although
C
anyway
D
otherwise