Some of the people often ask the same question the air has been polluted.
#30604
A
whether
B
if
C
that
D
where
推荐题目
___________there are many different types of food, some animals spend their lives eating only one type.
#31689
A
Since
B
Unless
C
Once
D
While
Everything was placed exactly ________ it used to be before she left the laboratory.
#30251
A
why
B
when
C
where
D
though
Yao Ming made it clear that he would never consider retiring from the NBA he could recover his health.
#33368
A
as long as
B
as far as
C
as well as
D
as soon as