[ngram] How to recognize informative n-grams in a corpus?

['Amir H. Jadidinejad' amir.jad...@yahoo.com [ngram]]

Hi,

I have a corpus of 3K short text documents. I’m going to recognize the most 
informative n-grams in the corpus.
Unfortunately, I can’t find a straight way from the documents. Would you please 
help me?

Kind regards,
Amir H. Jadidinejad