At the preface part, the author discusses the complexity and diversity of joint act of tort including the subject diversity, and identification of behavior and effect, inseparability of liability.

• 在引言部分，文章从共同侵权行为主体的复数性、行为和结果的共同性以及责任的不可分性谈起，认识共同侵权行为本身的复杂性和多样性。