______environmental damage is done，it takes many years for the ecosystem to recover.
#80690
A
Eyen if
B
If only
C
While
D
Once
推荐题目
_______ is known to us, the dragon stands for China ______the bear symbolizes Russia.
#30650
A
It; but
B
As; while
C
What; while
D
It; when
________， the car stopped all at once.
#31625
A
Seeing a boy lying on the ground
B
On seeing a boy sitting on the road
C
The driver saw a boy standing on the road
D
The minute the driver saw a boy seated on the road
The next day, the group of villagers had not gone very far they entered a very narrow passage betweentwo mountains．
#31567
A
when
B
while
C
until
D
after
My mother is always warning me when I go out, “Don’t get off the bus ____it is stopping.”
#32320
A
until
B
before
C
while
D
After
_______ you have got the news about him, I won’t hold it back from you.
#31730
A
Even though
B
Now that
C
In case
D
As if