i had a little trouble____english grammarA learn B learned C learning D to learn怎么选,为什么

问题描述:

i had a little trouble____english grammar
A learn B learned C learning D to learn
怎么选,为什么

C
没有为什么,只要记住 I have trouble 后面一定要跟着动词的 ing形.
e.g.
I have trouble concentraing in class.
我很难上课时集中思想.