保證 先訴抗辯權 職務保證 用益物權 物權的自由與效率 物權的安定與安全 占有 動產善意取得 扶養義務減免 子女稱姓 消滅時效 誠實信用原則 契約相對性 Guaranty Guarantor's right to refuse performance Employment guaranty Usufructuary rights Freedom and efficiency of property rights Stability and security of property rights Possession Bona fide emptor for personal property Exemption or relief of the obligation of maintenance Determination of children's surname Extinctive prescription Principle of good faith Privity of contrat