---How much difficulty did you have________________ this problem?
---_____________. It's quite easy.
A.to solve, Nothing | B.solving; None | C.to solve, None | D.solving; Nothing |
---How much difficulty did you have________________ this problem?
---_____________. It's quite easy.
A.to solve, Nothing | B.solving; None | C.to solve, None | D.solving; Nothing |