The design and implementation of an Intelligent Web-based Interactive Language Learning (IWiLL) system to support English learning on the Internet is described. We designed two kinds of learning environments: (1) interactive English writing environment and (2) mining movies for real English. These are intended to improve learners' basic language skills such as listening, reading, and writing. In addition, the system also offers authoring tools that facilitate teachers' content preparation. The system not only provides multimedia learning environments for users, but also builds a learner corpus, an archive of annotated English texts written by learners for whom English is a second language. Further analysis of the learner corpus creates the potential to detect the users' persistent errors and then provide adequate help to the users.