我不懂

• I don't get it.

例句

1. 我不懂那种没意思的玩意儿。
   I don't dig that crazy stuff.
2. 我不懂他们的语言，你得当翻译了。
   I don't understand their language; you'll have to act as interpreter.
3. 我不懂这个词是什么意思。
   I don't understand what the word means.