合同的变更：指在合同成立后，对合同内容进行的修改和补充，这不会改变合同主体，但会使合同内容发生变化。
合同的转让：指在不改变合同内容的前提下，合同关系的一方将其合同权利、义务全部或部分地转让给第三人，这会导致合同主体的变化。
合同的变更和转让
Modification and Transfer of Contracts
1. 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。
参考译文：The parties may modify their contract upon agreement reached through consultation.
Where laws and administrative regulations provide that the modification of a contract shall go through the procedures of approval and registration, such provision shall govern.
2. 当事人对合同变更的内容约定不明确的，推定为未变更。
参考译文：If any particulars of a contract modified upon agreement between the parties are not definite, no modification of the contract shall be deemed to have been made.
3. 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：
（1）根据合同性质不得转让；
（2） 按照当事人约定不得转让；
（3）依照法律規定不得转让。
参考译文：The creditor may assign all or part of his rights under the contract to a third person, except in any of the following circumstances:
(1) by nature of the contract such rights are not assignable;
(2) the parties have agreed that such rights may not be assigned;
(3) the law provides that such rights may not be assigned.
4. 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；
参考译文：If the creditor assigns his rights, it shall notify the debtor. Such assignment without notification shall be invalid as far as the debtor is concerned.
The creditor may not revoke the notification of the assignment of his rights, unless otherwise agreed by the assignee.
5. 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。
参考译文：When the creditor assigns his rights, the assignee shall also acquire the incidental rights in connection with the claim, unless such incidental rights are exclusive to the creditor.
6. 債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。
参考译文： After receiving the notice of the assignment of the claim, the debtor may initiate against the assignee the defense which he had against the assignor.
7. 債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。
参考译文：If at the time of receipt of the notice of the assignment of the claim the debtor has a claim against the assignor and the claim will mature before or at the same time as the assigned claim, the debtor may set off such claim against the assignee.
8.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。
参考译文： If the debtor intends to transfer all or part of his obligations under the contract to a third person, such transfer shall be subject to the consent of the creditor.
9. 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。
参考译文：When the debtor transfers his obligations, the new debtor may initiate against the creditor the defense which the original debtor had against the creditor.
10. 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。
参考译文：When the debtor transfers his obligations, the new debtor shall bear the incidental liabilities in connection with the primary liability, unless such incidental liabilities are exclusive to the original debtor.
