【正文】 a splementary agreement cannot be reaed, su terms shall be determined in accordance with the relevant provisions of the contract or the transaction practices.　　Article 62 Where certain contents agreed on by the parties in the contract are ambiguous and cannot be determined in accordance with the provisions in Article 61 of this Law, the following provisions shall be applied: 　　 (1)if quality requirement is not clear, performance shall be in accordance with the state standard or industry standard。 　　 (2) a party having the right to revoke the contract explicitly expresses or conducts an act to waive the right after it knows the revoking causes.　　Article 56 A contract that is null and void or revoked shall have no legally binding force ever from the very beginning. If part of a contract is null and void without affecting the validity of the other parts, the other parts shall still be valid.　　Article 57 If a contract is null and void, revoked or terminated, it shall not affect the validity of the dispute settlement clause whi is independently existing in the contract.　　Article 58 The property acquired as a result of a contract shall be returned after the contract is confirmed to be null and void or has been revoked。s court or an arbitration institution to modify or revoke it.　　 Where a party requests for modification, the people39。s true intentions through the use of fraud, coercion, or exploitation of the other party39。s court or an arbitration institution to modify or revoke the following contracts: 　　 (1) those concluded as a result of significant misconception。 　　 (5) violating the pulsory provisions of laws and administrative regulations.　　Article 53 The following exception clauses in a contract shall be null and void: 　　 (1) those that cause personal injury to the other party。 　　 (3) an illegitimate purpose is concealed under the guise of legitimate acts。 properties, and the principal ratifies the act afterwards or the person without of disposal has obtained the after concluding a contract, the contract shall be valid.　　Article 52 A contract shall be null and void under any of the following circumstances: 　　 (1) a contract is concluded through the use of fraud or coercion by one party to damage the interests of the State。s statutory agent.　　 The counterpart may urge the statutory agent to ratify the contract within one month. It shall be regarded as a refusal of ratification that the statutory agent does not make any expression. A bona fide counterpart has the right to withdraw it before the contract is ratified. The withdrawal shall be made by means of notice.　　Article 48 A contract concluded by an actor who as no of agency, who oversteps the of agency, or whose of agency has expired and yet concludes it on behalf of the principal, shall have no legally binding force on the principal without ratification by the principal, and the actor shall be held liable.　　 The counterpart may urge the principal to ratify it within one month. It shall be regarded as a refusal of ratification that the principal does not make any expression. A bona fide counterpart has the right to withdraw it before the contract is ratified. The withdrawal shall be made by means of notice.　　Article 49 If an actor has no of agency, oversteps the of agency, or the of agency has expired and yet concludes a contract in the principal39。s statutory agent, but a pure profitmaking contract or a contract concluded whi is appropriate to the person39。 　　 (2) deliberately concealing important facts relating to the conclusion of the contract or providing false information。 　　 (4) the offeree makes substantial anges to the contents of the offer. 　　Article 21 An acceptance is the expression of an intention to by the offeree to assent to the offer. 　　Article 22 The acceptance shall be made in the form of a notice, except where acceptance may be made by an act on the basis of customary business practice or as expressed in the offer. 　　Article 23 An acceptance shall rea the offeror within the time limit prescribed in the offer.　　 Where no time limit is prescribed in the offer, the acceptance shall rea the offeror in accordance with the following provisions: 　　 (1) if the offer is made in dialogues, the acceptance shall be made immediately unless otherwise agreed on by the parties。 　　 (2) the offeror revokes the offer in accordance with the law。s systems shall be regarded as the time of arrival. 　　Article 17 An offer may be withdrawn. The withdrawal notice shall rea the offeree before or at the same time when the offer arrives. 　　Article 18 An offer may be revoked. The revocation notice shall rea the offeree before it has dispated a notice of acceptance. 　　Article 19 An offer may not be revoked, if　　 (1) the offeror indicates a fixed time for acceptance or otherwise explicitly states that the offer is irrevocable。 　　 (2) it indicates that the offeror will be bound by the expression of intent in case of acceptance by the offeree.　　Article 15 An invitation for offer is an expression of an intent to invite other parties to make offers thereto. Mailed price lists, public notices of auction and tender, prospectuses and mercial advertisements, etc. are invitations for offer.　　 Where the contents of a mercial advertisement meet the requirements for an offer, it shall be regarded as an offer. 　　Article 16 An offer bees effective when it reaes the offeree.　　 If a contract is concluded through datatelex, and a recipient designates a specific system to receive the datetelex, the time when the datatelex enters su specific system shall be the time of arrival。 　　 (7) liability for brea of contract。 　　 (5) price or remuneration。 　　 (3) quantity。s Republic of ina on Mar 15, 1999 and effective as of October 1, 1999) 公布日：19990315 　施行日：19991001 　公布：全國人民 　　Contents　　General Provisions　　 apter 1 General Principles　　 apter 2 Conclusion of Contracts　　 apter 3 Validity