It never _____ humans until the mid1990s that some animals can be cloned.
#92718
A
occur
B
is occurred
C
occurred to
D
occurred
推荐题目
There will be a discussion tomorrow,all those who want to ,please raise your hands.
#95223
A
join
B
take part
C
take a part
D
take part in
Though we are not walking slowly, I still think that it won’t be _________ he _________up with us.
#92357
A
long before; catches
B
before long; catches
C
for long; caught
D
long until; will catch
--- Hey, Tom．I think I am quite familiar with these photographs．--- It is impossible for anyone_________ them before, because Mr．Newman had them developed today．
#93607
A
having seen
B
to have seen
C
to see
D
seeing
It is reported that women with demanding jobs are almost __________ to suffer a heart attack .
#93356
A
as likely twice
B
likely twice as
C
twice likely as
D
twice as likely