Part focuses on the related issue concerning the protection of the obligee and the third party ' s interests when the cud is valid based on part ii , and , through the analysis of the several specific systems of the cud in china ' s contract law , demonstrates that there is legal base for the validity of the cud , which effectively protects transaction safety , harmonizes the balance between the static and dynamic safety , and is also in accordance with the acquisition with goodwill . part analyses the reasons why the distortion of the cud comes into being 通过合同法分则中几种具体的无权处分行为制度的分析可以对无权处分行为有效性提供法律上的支持，并且把它和善意取得制度联系起来，指出善意取得制度的适用是以无权处分行为的有效性为前提的，创门属于不同的法域，适用不同的法律规制，善意、恶意绝不能成为决定合同效力的依据，应该把无权处分行为有效作为善意取得制度适用法律上的原因。
The restructure of labor contract enforcement system must start from protecting labor inclinedly and trying to maintain labor contract enforcement , loosing the valid factor of labor contract , affirming the law enforcement of oral and tacit labor contract , and redefining facture labor relationship for respecting the fact of the fulfilled relation of working 劳动合同效力制度的重构,必须从倾斜保护劳动者、尽量维护劳动合同效力的价值取向出发,放宽劳动合同的有效要件,肯定口头、默示形式劳动合同的法律效力,并重新定义事实劳动关系,尊重劳动关系的实际履行。
