You should inspect the wheels regularly, and replace them ______ they cause you trouble.
#31371
A
while
B
as
C
before
D
until
推荐题目
Most probably it will be another 7 hours _____ you can have next meal, so each of you must have your stomach full.
#30777
A
since
B
when
C
after
D
before
—How are things going, Jenny?—They have set out to deal with the present situation ______ they think deserves their immediately attention.
#31130
A
what
B
where
C
when
D
which
______ we have confidence and determination, we can win the match.
#30756
A
Once
B
Since
C
Unless
D
As long as
Tim is always lying, thus no one will believe _______ he says.
#34810
A
no matter what
B
why
C
which
D
whatever
Wind power is an ancient source of energy _____ we may return in the near future.
#33026
A
to which
B
by which
C
from which
D
on which