Ellen was a painter of birds and of nature，________，for some reason，had withdrawn from all human society.(2012·浙江，17)
#30487
A
which
B
who
C
where
D
whom
推荐题目
____ regular exercise is very important, it’s never a good idea to exercise too close to bedtime.
#30024
A
It
B
As
C
Although
D
Unless
The fact that smoking is harmful to health is__________ most smokers admit．
#32340
A
what
B
whether
C
where
D
that
We were having a meeting _________ suddenly someone knocked at the door.
#32482
A
because
B
when
C
as
D
while