World CALL Language Links Library. Computer-Assisted Language Learning to help students, teachers and researchers to improve their language learning or teaching.
Research Tools
Web Frequency Indexer. Cut and paste an article, you will get a list of words used in the article with frequency numbers.
Web Concordancer. You can search an online corpus for a word and display all the sentences in which the word occurs.
Corpus of Contemporary American English. The largest freely-available corpus of English, and the only large and balanced corpus of American English with over 400 million words, 1990-2010.