第七十七条　当事人协商一致，可以变更合同。法律、行政法规规定变更合同应当办理批准、登记等手续的，依照其规定。

 Article 77 The parties may modify the contract upon consensus through consultation.

Where provisions of laws and administrative regulations require the modification of a contract to go through approval and registration procedures, such provisions shall govern. 

第七十八条　当事人对合同变更的内容约定不明确的，推定为未变更。

Article 78    A contract shall be assumed as not having been modified if the content of the modification of the contract is not clearly agreed upon by the parties.

第七十九条　债权人可以将合同的权利全部或者部分转让给第三人，但有下列情形之一的除外：

（一）根据合同性质不得转让；

（二）按照当事人约定不得转让；

（三）依照法律规定不得转让。

Article 79 A    creditor may transfer its rights under a contract in whole or part to a third party, except in any of the following circumstances:

(1) the transfer is not allowed according to the nature of the contract;

(2) the transfer is not allowed according to the agreement between the parties; or

(3) the transfer is not allowed according to the provisions of laws.

第八十条　债权人转让权利的，应当通知债务人。未经通知，该转让对债务人不发生效力。债权人转让权利的通知不得撤销，但经受让人同意的除外。

Article 80    Any transfer of rights by a creditor shall be notified to the debtor. The    transfer shall not bind the debtor without such notification.

A creditor may not revoke the notice of its transfer of rights, except with the consent of the transferee.

第八十一条　债权人转让权利的，受让人取得与债权有关的从权利，但该从权利专属于债权人自身的除外。

Article 81    Where a creditor transfers its rights, the transferee shall also obtain the accessory rights related to the creditor's rights, except for cases the accessory rights exclusively belonging to the creditor.

第八十二条　债务人接到债权转让通知后，债务人对让与人的抗辩，可以向受让人主张。

Article 82    After a debtor has received a notice on the transfer of creditor's rights,    the debtor may address its plea against the transferor to the transferee.

第八十三条　债务人接到债权转让通知时，债务人对让与人享有债权，并且债务人的债权先于转让的债权到期或者同时到期的，债务人可以向受让人主张抵销。

Article 83 When a debtor receives a notice on the transfer of creditor's rights, and if the debtor has creditor's rights over the transferee and the creditor's rights of the debtor are matured before or at the    same time as the transferred creditor's rights, the debtor may advocate to the transferee an offset.

第八十四条　债务人将合同的义务全部或者部分转移给第三人的，应当经债权人同意。

Article 84    If a debtor intends to transfer its obligations under a contract in whole or in part to a third party, consent shall be obtained from the creditor.

第八十五条　债务人转移义务的，新债务人可以主张原债务人对债权人的抗辩。

Article 85    If a debtor transfers its obligations, the new debtor mayadvocate the original debtor's plea against the creditor.

第八十六条　债务人转移义务的，新债务人应当承担与主债务有关的从债务，但该从债务专属于原债务人自身的除外。

Article 86    If a debtor transfers its obligations, the new debtor shall assume the    accessory debts related to the principal debts, except for the accessory debts exclusively assumed by the original debtor.

第八十七条　法律、行政法规规定转让权利或者转移义务应当办理批准、登记等手续的，依照其规定。

 Article 87 Where provisions of laws and administrative regulations require the transfer of rights or obligations to go through approval and registration procedures, such provisions shall govern.

第八十八条　当事人一方经对方同意，可以将自己在合同中的权利和义务一并转让给第三人。

 Article 88 Either    party may, with the consent of the other party, transfer its rights    together with its obligations under the contract to a third party.

第八十九条　权利和义务一并转让的，适用本法第七十九条、第八十一条至第八十三条、第八十五条至第八十七条的规定。

Article 89 When    rights together with obligations are transferred, the provisions of Article 79, Articles 81 to 83, and Articles 85 to 87 of this Law shall apply.

第九十条　当事人订立合同后合并的，由合并后的法人或者其他组织行使合同权利，履行合同义务。当事人订立合同后分立的，除债权人和债务人另有约定的以外，由分立的法人或者其他组织对合同的权利和义务享有连带债权，承担连带债务。

Article 90 Where a party merges after the execution of the contract, the legal person or the organization arising from the merger shall exercise the rights under the contract and fulfill the obligations under the contract. Where a party splits after the execution of the contract, unless the creditor and the debtor stipulate otherwise, the legal persons or the organizations arising    from the split shall enjoy joint and several creditor's rights under the contract and assume joint and several liabilities under the contract.

第77至90条是“合同变更”和“合同转让”制度，以上14条分别规定了：

1.合同变更程序（协商+登记、批准）

2.未变更推定（内容不明确）

3.债权转让（1原则:可以；3例外：合同性质+事先约定+法律禁止；1程序:通知；3要点:从权利+抗辩权+抵销权。）

4.债务转让（1原则:同意；2要点:从权利+抗辩权。）

5.合并分立与债权债务转让（合并：合并后主体继承；分立：连带债权，连带债务。）

1.（合同）变更。合同、法律的“变更”常用amend，modify，revise几词。比如，现行《公司法》公布主席令有这么一句“The Companies Law of the PRC has been revised and adopted at the 18th Meeting    of……”。注意，不能用rectify一词。变更合同的形式通常是supplementary agreement或side letter。                                       

 2.（合同）转让。合同、权利的“转让”，官方译本翻译为“transfer”，个人认为翻译错误。有必要区分assign和transfer的差别。assign／assignment表示to transfer property rights to sb in accordance with laws,而transfer／transference仅表示to hand over the possession of property, etc.翻译为中文，也就是说，assign是“转让权利”,而transfer是“交付物品”和deliver类似。英文合同，有个“转让与分包”标准条款，其对应的词汇正是assignability。

3.主权利、从权利、主债务、从债务。Principal    right, accessory right, principal debt, accessory debt。合同分类中，主合同与从合同准确英文表述也是principal contract and accessory contract。

引申一点，担保合同涉及的民事主体通常包括“担保人、主债务人、受益人"，其准确英文术语分别为“the guarantor，the principal obligor，the beneficiary”，大家在商务谈判以及翻译等场合切记使用准确。

4.主张（权利）。可用advocate, claim, assert, address, 实务高频用词。

5.抗辩。可译为plea, plead, demur。辞典解释，plea意为an allegation of fact in civil litigation made in response to a claim。Plead强调make an allegation in an action or other legal proceeding, especially answer the previous pleading of the other party by denying facts therein stated or by alleging new facts。Demur则表示a formal objection to an opponent's pleadings。

6.（债权）到期。可以使用due，mature，但不可以是expire。理由请参加2016年6月13日（昨天）关于《合同法》第70-76条“法言法语”部分第5点、第3小分点的讲解。

7.（债权）抵消。使用offset没争议，其含义为compensate for or counterbalance。

8.连带债权、连带债务。Exercise the right and assume the obligation jointly and severely。实务中常用的“连带责任”是joint and several liability。

9.转让人、受让人。分别为transferor和transferee，assignor和assignee。在本公众号第一篇原创文章《法律英语基础》关于法律英语“句法特征”的描述中，作者提到过合同等法律文件中代词一般用间接代词而少用人称代词以避免混淆和误解，此处表述便是这一特点的很好反映。

1. amend，modify，revise，rectify

2. assign，transfer，deliver

3.Principal right, accessory right, principal debt, accessory debt,principal    contract，accessory contract，the guarantor，the principal obligor,the ben   eficiary

4. advocate, claim, assert，address

5. plea, plead, demur

6. due，mature，expire

7. offset,compensate for,counterbalance

8. Joint and several liability,exercise the right and assume the obligation jointly and severely

9. transferor,transferee，assignor，assignee