Besides this, the system is perfectly integrated in the TEITOK environment: it allows for complex queries at the token level using all the information stored in the corpus through CQP; it makes possible a visual representation of the learner text corrected at three different levels (orthographic, grammatical and lexical).
taking into account what we discussed in section 1, it is clear that this system presents some problems for error annotation: it only works at the token level 2 ; it offers a limited categorization and description of errors types; and it is limited to three linguistic areas, while some errors go beyond those areas.