Translation of "Slang" in Chinese

It's fun to learn slang words in foreign languages.

学习外语里的俚语很有趣。

I can understand most of what they say, but I don't understand the slang they use (in their speech).

我大部分能听懂他们说的话，但是听不懂他们说的俗语。

Because Chinese blogs use a lot of slang, I usually don't understand them that well, but I still think it's good for my Chinese.

因为中文的博客常常是用许多俚语写的，我往往看得不太懂，但是我还是觉得这个活动对我的中文水平有好的影响。