life will continue on the earth for millions of years to come will depend on the problem of pollution can be solved.
#30117
A
How /whether
B
That/that
C
Whether / if
D
Whether / whether
推荐题目
Colin was about to get off the camel ________ a child ran towards him.
#31552
A
while
B
when
C
as
D
since
The notice says _________ you are, you must show your tickets to enter the exhibition.
#31117
A
whoever
B
who
C
however
D
Whom
I was about to inform you of the sudden change ______an unexpected visitor came.
#30562
A
because
B
before
C
when
D
unless
—Look, the paint is starting to come off ____ the wall is damp.—Well, we'd better have the wall repainted some day.
#31419
A
when
B
where
C
if
D
once
On Christmas Eve, children are eager to know _______Father Christmas comes and puts presents into their stockings．
#30107
A
that
B
what
C
where
D
how