Abstract 1. Introduction 2. Theoretical Background 2.1. Theme and subject 2.2. Theme and subject in Korean 2.3. Hypotheses and definitions 3. The Experiment 3.1. Method 3.2. The database 4. Results 4.1. Subject assignment and theme 4.2. Choice of particles and theme 4.3. Particles as a referenctial management device. 5. Conclusion References