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

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

A. to understand; reading                 

B. understanding; reading          

C. to understand; to read                  

D. understanding; to read

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

--- Remember       it three times at least.

---Mr Wang, I have trouble ________ the text.
---I’m sure you can, but remember ________ it at least three times.

---Mr. Wang, I have trouble ______the test.
---Remember ________ it three times at least.
to understand; reading
B. understanding; Reading
C. understanding; to read
D. to understand; to understand