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第四章 合同的履行
Chapter IV
Performance of Contracts
第五百零九条 当事人应当按照约定全面履行自己的义务。
Article 509
The parties shall fully perform their respective obligations as agreed in the
contract.
当事人应当遵循诚信原则，根据合同的性质、目的和交易习惯履行通知、协助、保密等义务。
The parties shall comply with the principle of good faith, and perform such
obligations as sending notification, rendering assistance, and keeping
confidentiality in accordance with the nature and purpose of the contract and
the course of dealing.
当事人在履行合同过程中，应当避免浪费资源、污染环境和破坏生态。
The parties shall avoid wasting the resources, polluting the environment, or
damaging the ecology in the course of performance of the contract.
第五百一十条 合同生效后，当事人就质量、价款或者报酬、履行地点等内容没有约定或者约定不明确的，可以协议补充；不能达成补充协议的，按照合同相关条款或者交易习惯确定。
Article 510
After a contract becomes effective, where the parties have not agreed on such
contents as the quality, price or remuneration, or the place of performance, and
the like, or the relevant agreement is unclear, the parties may make a
supplementary agreement; where the parties fail to reach a supplementary
agreement, such contents shall be determined according to the relevant clauses
of the contract or the course of dealing.
第五百一十一条 当事人就有关合同内容约定不明确，依据前条规定仍不能确定的，适用下列规定：
Article 511
Where an agreement between the parties concerning the contents of their contract
is unclear and such contents cannot be determined according to the provisions of
the preceding Article, the following provisions shall be applied:
（一）质量要求不明确的，按照强制性国家标准履行；没有强制性国家标准的，按照推荐性国家标准履行；没有推荐性国家标准的，按照行业标准履行；没有国家标准、行业标准的，按照通常标准或者符合合同目的的特定标准履行。
(1) where the quality requirements are not clearly stipulated, the contract
shall be performed in accordance with a mandatory national standard, or a
recommendatory national standard in the absence of a mandatory national
standard, or the standard of the industry in the absence of a recommendatory
national standard. In the absence of any national or industrial standard, the
contract shall be performed in accordance with the general standard or a
specific standard conforming to the purpose of the contract.
（二）价款或者报酬不明确的，按照订立合同时履行地的市场价格履行；依法应当执行政府定价或者政府指导价的，依照规定履行。
(2) where the price or remuneration is not clearly stipulated, the contract
shall be performed in accordance with the market price in the place of
performance at the time the contract is concluded. Where a government-set or
government-guided price shall be applied as required by law, the contract shall
be performed at such a price.
（三）履行地点不明确，给付货币的，在接受货币一方所在地履行；交付不动产的，在不动产所在地履行；其他标的，在履行义务一方所在地履行。
(3) where the place of performance is not clearly stipulated, the contract shall
be performed at the place of the party receiving money where payment of money is
involved, or, where real estate is to be delivered, at the place where the real
estate is located. For other subject matters, the contract shall be performed at
the place where the party performing the obligation is located.
（四）履行期限不明确的，债务人可以随时履行，债权人也可以随时请求履行，但是应当给对方必要的准备时间。
(4) where the period of performance is not clearly stipulated, the debtor may
perform the obligation at any time, and the creditor may request the debtor to
perform at any time, provided that he shall give the debtor a period of time
necessary for preparation;
（五）履行方式不明确的，按照有利于实现合同目的的方式履行。
(5) where the manner of performance is not clearly stipulated, the contract
shall be performed in a manner conducive to realizing the purpose of the
contract; and
（六）履行费用的负担不明确的，由履行义务一方负担；因债权人原因增加的履行费用，由债权人负担。
(6) where the allocation of expenses for performance is not clearly stipulated,
the expenses shall be borne by the party performing the obligation; where the
expenses for performance are increased due to the creditor’s reason, the
creditor shall bear the increased part of the expenses.
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