问题
选择题
---Mr. Wang, I have trouble the text.
--- Remember it three times at least.
A．to understand; reading
B．understanding; reading
C．understanding;to read
D．to understanding; to read
答案
答案：C
have some trouble in doing sth，第一空用动名词，故将A的排除，根据上下文，可知后文说的是记得曾经做某事，故用动名词，故选答案为C