This study aims to evaluate the practicality and reliability of the selection of derivational forms in Korean National Curriculum of English and examines the effect of the derivational regulation on government-authorized English textbooks used in middle and high school. The current National Curriculum issued the guideline for vocabulary use and selection in the textbooks and regulated derived words with 11 affixes not counted as new words (Chang, 2007). For the research, suffixed word list was developed based on high frequency 14,000 word families in BNC (Nation, 2004) and it was loaded onto the RANGE (Heatley & Nation, 2002). By using the developed suffix analysis tool, 28 newly revised textbooks from middle and high school curriculum were analyzed and three corpora including Brown Corpus, Open American National Corpus (OANC), and L2 corpus were investigated to suggest improved regulation of derivational forms. As a result, the guideline for the derivational regulation in the Curriculum is found to require more consistent research. For the purpose, four levels of graded suffixes were suggested for the future English curriculum revision.

I. INTRODUCTION
II. THEORETICAL BACKGROUND
III. RESEARCH DESIGN
IV. RESULTS AND DISCUSSION
V. CONCLUSION

• Jiho Park(International Graduate School of English)