WriteBetter is a writing assistant that leverages the Data-Driven Learning (DDL) approach. DDL refers to an approach to learning foreign languages in which students discover language patterns or rules autonomously by exploring a large number of sentences written by qualified speakers of English. To do so, WriteBetter offers a function through which students can search for words to discover how to use them by exploring real sentences that contain those words. WriteBetter also has a function with which students can explore the most frequent language structures related to the words searched. Students can also enrich their texts by looking up words in an integrated dictionary, which provides definitions, synonyms, antonyms, and examples. This dictionary is WordNet, a large lexical database of English published by Princeton University. Another function of WriteBetter is a translator in nine languages, with which students can understand the words they are searching for through contextualised human-made translations. The corpora that WriteBetter uses are Wikipedia articles, and around 3,000 public domain English books.