Abstract 1. Problem 2. Verb Classes of Ergatives and Middles 2.1. Some Properties of Ergatives and Middles 2.2. Verb Classes in Levin (1993) and Chung (2002) 3. Ergative Verbs and Middle Verbs 3.1. Ergative verbs are middle verbs 3.2. Ergative Verbs 3.3. Middle Verbs 3.4. Verb Classes and Verb Alternations 4. Conclusion References Appendix