Stephen Hawking has expressed his opinion ___ humans might one day be able to make spaceships capable of such speeds that time on board would slow down．
#69972
A
that
B
whom
C
which
D
what
推荐题目
There are some warnings in some countries ______ over exploitation of underground water has caused the decline of wetland and increase of desertification.
#67588
A
which
B
where
C
what
D
that
I don’t think he will make a superstar like Cristiano Ronaldo. He just lacks it takes to be a professional soccer player.
#69995
A
Which
B
that
C
what
D
who
If we ______ take environmental problems seriously, the earth _______ worse and worse.
#40979
A
don’t; will be
B
won’t; isn’t
C
won’t; is
D
don’t; won’t be
Evidence has been found through years of study __________ children’s early sleeping problems are likely to continue when they grow up.
#67550
A
why
B
how
C
that
D
whether
Have you ever seen any trees ________ leaves were black because of the polluted air?
#66808
A
whose
B
that
C
which
D
who