How to translate: “对我来说，北方人的口音和语速 {makes it difficult for me to understand them}"?
对我来说，北方人的口音和语速 makes it difficult for me to understand them.


This translation sounds more like English grammar. Chinese people will say


  对我来说，北方人有口音，语速很快，很难听明白。


Hope this could be of some help.