English teachers who teach English as a second language are confronted with a lot of spelling errors. A submitted homework assignment can be passed to a spell checker and could reject a submission. In teaching western languages to students, from a first language where the text formating rules are totally different (e.g., Japanese), a format checker could also reject homework with wrong punctuation [SC96]. Teachers could also specify tests which are homework-specific: like a minimum/maximum number of words, inclusion of certain keywords, etc.