-This problem is very difficult.       -I know,but Jack has           working it out. 
#38799
A
succeed in
B
succeeds in
C
succeeding in
D
succeeded in
推荐题目
— How long ________ they ________ the English Club?  — For almost one year.
#40116
A
have; been
B
have; been in
C
did; join
D
did; join in
Look! These clips _______ your favourite T-shirt.
#41548
A
matches
B
match
C
matching
D
matches with