In auditing (审计), as in other fields of knowledge, there are fundamental relationships that are essential to a comprehensive understanding of the subject. The basic relationships of auditing are discussed in the three chapters that comprise Part I of this book. Chapter 1, describe the function of auditing in society, the auditor’s standard report, and the nature of the public accounting profession. In Chapter 2, consideration is given to quality control, the audit process, and audit planning. Chapter 3 explains the types of audit evidence that may be obtained by the auditor in an audit engagement and the importance of documenting the auditor’s work and findings in audit working papers. How many aspects do Chapter 3 concerns _________________________________________.