Up to now, no one has come up with a（n） explanation of why dinosaurs died out, and it remains a mystery．
#11239
A
astonishing
B
amusing
C
convincing
D
puzzling
推荐题目
It’s said that the power plant is now ______large as what it was.
#11667
A
twice as
B
as twice
C
twice much
D
much twice
One way to ________ species under threat of extinction—whatever the cause—is to remove them to zoos or parks and feed them there.
#10720
A
betray
B
resist
C
preserve
D
abandon
I think he is _____ to tell us the secret, but I’m not sure.
#14425
A
possible
B
likely
C
impossible
D
certain
No one is allowed, no matter who he is, _____ the room unless he has a permit.
#12244
A
enters
B
to enter
C
entering
D
entered
The two villages have a close ________ and often help each other.
#10833
A
bond
B
shade
C
behaviour
D
bond