Scientists have made a major ____ in cancer research. 
#83068
A
break-in
B
breakthrough
C
breakup
D
breakdown
推荐题目
Since the summary has been made, we shall ________ the details.
#72426
A
look up to
B
get down to
C
come up with
D
end up with
The folks were delighted at the message of their relatives _______ that mine explosion.
#72957
A
survived
B
to survive
C
were surviving
D
surviving
Great changes ___ in the recent years.
#80867
A
are taking their place
B
have taken place
C
have been taken place
D
take place