-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
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----      your son        a computer?------No.He        one this summer vacation.
#36548
A
Has; bought; will buy
B
Did; buy; bought
C
Does; buy; bought
D
Does; buy; will buy