1. Introduction
2. Methodology and Corpus
3. Findings: Error Patterns and Interference
3.1 Pronunciation Error and Interference
3.2 Orthography Error and Interference
3.3 Particle Error and Interference
3.4 Verbal Suffix Error and Interference
3.5 Tense Error and Interference
3.6 Politeness Expression Error and Interference
3.7 Word Order Error and Interference
3.8 Vocabulary Error and Interference
4. Conclusion
References