N-GRAMS
from the COCA and COHA corpora of American English
home compare to Google samples using the data historical (COHA) non-English free downloads purchase


These n-grams are based on the largest publicly-available, genre-balanced corpus of English -- the 425 million word Corpus of Contemporary American English (COCA). With this n-grams data (2, 3, 4, 5-word sequences, with their frequency), you can carry out powerful queries offline -- without needing to access the corpus via the web interface.

A few examples (from among an unlimited number of searches) might be:

 NOUN + NOUN sequences  three word strings with a preposition in the middle position
 VERB + the + NOUN sequences  two word strings, where the words begin or end with certain letters
 like + word + word  (potential) phrasal verb: VERB + ADV particle

The data is available in several different formats:

1 Free lists

1 million most frequent 2, 3, 4, and 5-grams
2 Inexpensive data sets

All n-grams that occur three times or more: 6.2 million 2-grams, 11.9 million 3-grams, and 8.3 million 4-grams
3 All 2, 3, and 4-grams

Up to 155 million distinct strings -- searchable by word form and part of speech (as above), and also lemma

If you're interested in the frequency of single words (including frequency by genre and sub-genre), or collocates (all words "near by" a given word), you might look at http://www.wordfrequency.info.