From space, the earth looks blue. This is ____about seventy-one percent of its surface is covered by water.
#30949
A
why
B
how
C
because
D
whether
推荐题目
My parents live in a small village. They always keep candles in the house ___ there is a power cut.
#79986
A
if
B
unless
C
in case
D
so that
The police said they would not give up looking into other possibilities ____they find out what happened.
#32173
A
as
B
while
C
until
D
although
