Flectcher's another powerful tool to extract n-grams:
kfNgram is a free stand-alone Windows program for linguistic research which generates lists of n-grams in text and HTML files. Here n-gram is understood as a sequence of either n words, where n can be any positive integer, also known as lexical bundles, chains, wordgrams, and, in WordSmith, clusters, or else of n characters, also known as chargrams. When not further specified here, n-gram refers to wordgrams. kfNgram also produces and displays lists of "phrase-frames", i.e. groups of wordgrams identical but for a single word.
http://miniappolis.com/KWiCFinder/kfNgramHelp.html#Download
kfNgram is a free stand-alone Windows program for linguistic research which generates lists of n-grams in text and HTML files. Here n-gram is understood as a sequence of either n words, where n can be any positive integer, also known as lexical bundles, chains, wordgrams, and, in WordSmith, clusters, or else of n characters, also known as chargrams. When not further specified here, n-gram refers to wordgrams. kfNgram also produces and displays lists of "phrase-frames", i.e. groups of wordgrams identical but for a single word.
http://miniappolis.com/KWiCFinder/kfNgramHelp.html#Download