Question

---Mr Wang, I have trouble ________ the text.  

---I’m sure you can, but remember ________ it at least three times.

1. A.
   to understand; reading
2. B.
   understanding; reading
3. C.
   to understand; to read
4. D.
   understanding; to read

Answer 1

D
have trouble doing sth表示做某事有难度或困难；remember to do sth表示记着去做某事。