【正文】 However, if, by virtue of the offer or as a result of practices which the parties have established between themselves or of usage, the offeree may indicate assent by performing an act, such as one relating to the dispatch of the goods or payment of the price, without notice to the offeror, the acceptance is effective at the moment the act is performed, provided that the act is performed within the period of time laid down in the preceding 19(1)A reply to an offer which purports to be an acceptance but contains additions, limitations or other modifications is a rejection of the offer and constitutes a counteroffer.(2)However, a reply to an offer which purports to be an acceptance but contains additional or different terms which do not materially alter the terms of the offer constitutes an acceptance, unless the offeror, without undue delay, objects orally to the discrepancy or dispatches a notice to that he does not so object, the terms of the contract are the terms of the offer with the modifications contained in the acceptance.(3)Additional or different terms relating, among other things, to the price, payment, quality and quantity of the goods, place and time of delivery, extent of one party39。s liability to the other or the settlement of disputes are considered to alter the terms of the offer 20(1)A period of time for acceptance fixed by the offeror in a telegram or a letter begins to run from the moment the telegram is handed in for dispatch or from the date shown on the letter or, if no such date is shown, from the date shown on the period of time for acceptance fixed by the offeror by telephone, telex or other means of instantaneous munication, begins to run from the moment that the offer reaches the offeree.(2)Official holidays or nonbusiness days occurring during the period for acceptance are included in calculating the , if a notice of acceptance cannot be delivered at the address of the offeror on the last day of the period because that day falls on an official holiday or a nonbusiness day at the place of business of the offeror, the period is extended until the first business day which 21(1)A late acceptance is nevertheless effective as an acceptance if without delay the offeror orally so informs the offeree or dispatches a notice to that effect.(2)If a letter or other writing containing a late acceptance shows that it has been sent in such circumstances that if its transmission had been normal it would have reached the offeror in due time, the late acceptance is effective as an acceptance unless, without delay, the offeror orally informs the offeree that he considers his offer as having lapsed or dispatches a notice to that 22 An acceptance may be withdrawn if the withdrawal reaches the offeror before or at the same time as the acceptance would have bee 23 A contract is concluded at the moment when an acceptance of an offer bees effective in accordance with the provisions of this 24 For the purposes of this Part of the Convention, an offer, declaration of acceptance or any other indication of intention “reaches” the addressee when it is made orally to him or delivered by any other means to him personally, to his place of business or mailing address or, if he does not have a place of business or mailing address, to his habitual III SALE OF GOODS Chapter I GENERAL PROVISIONSArticle 25 A breach of contract mitted by one of the parties is fundamental if it results in such detriment to the other party as substantially to deprive him of what he is entitled to expect under the contract, unless the party in breach did not foresee and a reasonable person of the same kind in the same circumstances would not have foreseen such a 26 A declaration of avoidance of the contract is effective only if made by notice to the other 27 Unless otherwise expressly provided in this Part of the Convention, if any notice, request or other munication is given or made by a party in accordance with this Part and by means appropriate in the circumstances, a delay or error in the transmission of the munication or its failure to arrive does not deprive that party of the right to rely on the 28 If, in accordance with the provisions of this Convention, one party is entitled to require performance of any obligation by the other party, a court is not bound to enter a judgement for specific performance unless the court would do so under its own law in respect of similar contracts of sale not governed by this 29(1)A contract may be modified or terminated by the mere agreement of the parties.(2)A contract in writing which contains a provision requiring any modification or termination by agreement to be in writing may not be otherwise modified or terminated by , a party may be precluded by his conduct from asserting such a provision to the extent that the other party has relied on that IIOBLIGATIONS OF THE SELLERArticle 30 The seller must deliver the goods, hand over any documents relating to them and transfer the property in the goods, as required by the contract and this of the goods and handing over of documentsArticle 31 If the seller is not bound to deliver the goods at any other particular place, his obligation to deliver consists:(a)if the contract of sale involves carriage of the goodsin placing the goods at the buyer39。s disposal at that place。(c)in other casesin placing the goods at the buyer39。s disposal at the place where the seller had his place of business at the time of the conclusion of the 32(1)If the seller, in accordance with the contract or this Convention, hands the goods over to a carrier and if the goods are not clearly identified to the contract by markings on the goods, by shipping documents or otherwise, the seller must give the buyer notice of the consignment specifying the goods.(2)If the seller is bound to arrange for carriage of the goods, he must make such contracts as are necessary for carriage to the place fixed by means of transportation appropriate in the