Chapter Four is a detailed report of an empirical study of writing errors conducted within the framework of Error Analysis. The procedure of the study was shown in this chapter, which includes hypothesis, error classification, error description and error analysis. 第四章详细地阐述了在错误分析理论框架下对学生作文中错误的实证性研究,具体包括预设、错误分类,错误描写及错误的研究。