．The fact has worried many scientists ______ the earth is becoming warmer and warmer these years.
#34793
A
what
B
which
C
that
D
though
推荐题目
Students should be encouraged to ______ their own opinions, ______ right or wrong.
#30814
A
present; whether
B
compare; no matter
C
announce; no matter
D
remark; whether
_A container weighs more after air is put in, ____proves that air has weight.
#80057
A
as
B
it
C
that
D
which
The dancers, all of _______ masks came off suddenly, gave us a great surprise.
#32153
A
their
B
whose
C
which
D
whom