1、 首先是唐纳德对山姆提出了一个要约， 要约的内容为 唐纳德想要为山姆建造一个露台。 山姆表示接受要约， 但是他把 唐纳德先生的邮箱搞错了， 所以表示接受要约的意思表示没有到 达唐纳德。Case analysis: Firstly, Donald provided an offer to Sam, which is about that Donald was trying to build a terrace for Sam. Sam accepted the offer. But he mistook Donalds mail box. So the offer that Sam accept
2、ed did not reach Donald s mail box.根据合同法第十六条： “要约到达受要约人时生效。 ”在案件中， 唐纳德的要约已经到达了受要约人山姆，所以此要约是生效的。Accord ing to Article 16 Effective ness of Offer, Offer throughElectro nic Message.An offer becomeseffective whenit reaches the offeree. In this case, Don aids offer has reached Sam,so the offer is effecti
3、ve.根据合同法第十八条：“要约可以撤销。撤销要约的通知应当在 受要约人发出承诺通知之前到达受要约人。 ”此案件中，由于受要约人山姆发出的承诺通知没有到达唐纳德， 所以唐纳德可以对要约进行撤销，即要约的撤销。Accord ing to Article 18 Revocati on of OfferAn offer may be revoked. The no tice of revocati on shall reachthe offeree before it has dispatched a no tice of accepta nee.In this case, Don aid coul
4、d withdraw the offer. Because thenotice of promise made by the offeror, Sam, did not reachDon ald.Questi on 1: Is Don ald en titled to withdraw its offer to builda patio for Sam? Why?问题1 :唐纳德是否有权撤销为山姆建造露台的要约，并说明理由。答案1 :唐纳德有权撤销该要约。 “要约 可以撤销。撤销要约的通知应当在受要约人发出承诺通知之前到达受要约人。”此案件中，由于受要约人山姆发出的承诺通知没有到达唐纳德，所以
5、唐纳德可以对要约进行撤销， 即要约的撤销An swer 1: Don aid is en titled to withdraw its offer to build a patio for Sam. The reason is as follows:An offer may be revoked. The no tice of revocati on shall reach the offeree before it has dispatched a no tice of accepta nee.In this case, Don ald could withdraw the offer. B
6、ecause the notice of promise made by the offeror, Sam, did not reach Don ald.Later on that day , Sam receives a call on his cellphone fromSally who offers to sell him her piano for 3,500. Samis very anxious to purchase the piano, but in response to the offer he says to Sally I ll give you 3 000 for
7、the piano. Sally refuses to barga in with Sama nd tells him blu ntly that the price is 3,500 if he wants to get the piano. Two hours later, Sam phones Sally agreeing to pay 3,500, but he is somewhat shocked to be told by Sally that she is no Ion ger in terested in deali ng with him and some one else
8、 is coming over to look at the pia no.山姆接到了一个来自萨莉的电话，萨莉说要以 3500英镑的价格把自己的钢琴卖给山姆。虽然山姆很想买这架钢琴，但是他说他想要一 3000 英镑的价格买萨莉的钢琴。萨莉拒绝与 山姆讨价还价，并且告诉山姆她的钢琴出价就是 3500 英镑。两 个小时以后，山姆打电话给萨莉说自己愿意以 3500 英镑的价格买她的钢琴，但是萨莉却说她不愿意与山姆 交易了，而且有另 外一个人正赶过来看这架钢琴。案情分析：Question 2: Can Saminsist that Sally sell the piano to him for 3,5
9、00?问题 2：山姆可以坚持让萨莉把钢琴以 3500 英镑的价格把钢琴 卖给他吗？并说明理由。答案 2：不能；理由如下：Answer 2: He can not. The reason is as follows: 首先是，萨莉通过电话向山姆发了一个要约， 表示愿意把自己的 钢琴以 3500 英镑的价格卖给山姆，但是山姆表示自己只想要出 3000 英镑买这架钢琴。民法总则对意思表示的生效规则作了规 定，以对话方式作出的意思表示，相对人知道其内容时生效。而 对话方式作出的意思表示， 是指通过面对面的谈话或者手语、 电 话或者在线即时通讯方式作出的意思表示。First, Sally sent an
10、 offer to Samover the phone, promising to sell her piano t o Samfor 3500, but Samsaid he wanted to spend 3,000 in buying the piano. The general rule of civil law enactsthe declaratio n of inten ti on which is expressed in a conv ersati onal manner becomes effective whe n they know the content. Decla
11、ratio n of i nten tio n by conv ersati ons refers to the means of expressi on through face-to-face conv ersati on or sig n Ian guage, telepho ne or on li ne in sta nt messag ing.根据合同法第二十条 有下列情形之一的，要约失效：（一）拒绝要约的通知到达要约人；（二）要约人依法撤销要约；（三）承诺期限届满，受要约人未作出承诺； （四）受要约人对要约的内容作出实质性变更。Article 20 Ext in guishme n
12、t of OfferAn offer is ext in guished in any of the followi ng circumsta nces:（i）The no tice of rejecti on reaches the offeror;（ii）The offeror lawfully revokes the offer;（iii）The offeree fails to dispatch its accepta nee at the endof the period for accepta nee;（iv）The offeree makes a material cha nge
13、 to the terms of the offer.本条是对要约失效的规定。 要约的失效，也可以称为要约的消灭 或者要约的终止，指要约丧失法律效力，要约人与受要约人均不 再受其约束。要约人不再承担接受承诺的义务， 受要约人亦不再 享有通过承诺使合同得以成立的权利。This section provides for the invalidation of an failure ofthe offer can also be called the eradication of the offer,thetermination of the offer or the loss of legal e
14、ffect of the offer.It means the offeror and the offere are no Ion ger bound by it.The offeror no Ion ger bears the obligati on to accept the promise, and the offen der no Ion ger enjoys the right to promise the con tract to be established.根据合同法第二十一条： “承诺是受要约人同意要约的意思表”示 OAccord ing to Article 21 Defi
15、n iti on of Accepta neeAn acceptanee is the offeree s manifestation of intention to asse nt to an offer.此案件中，山姆不同意以 3500英镑的价格买萨莉的钢琴。双方 通过电话作出的意思表示，所以当山姆拒绝以 3500英镑买萨莉的钢琴时，他们之间的要约失效。In this case, Samdid not agree to buy Sallys piano for 3500.As the two sides had a conv ersati on by teleph one, whe n S
16、amrefused to buy Sallys pia no for 3500, the offer was no Ion ger valid.作为使合同得以成立生效的承诺， 必须具备一定的条件：承诺必须由受要约人作出；承诺须向要约人作出；承诺的内容必须与要 约保持一致（承诺必须是对要约完全的、单纯的同意） ；承诺必 须在要约的有效期内作出。承诺如果对要约的内容进行实质性变 更，不能构成承诺而应视为新的要约。If a promise want to come into effect, certain conditions must be met. The promise must be mad
17、e by the offeree; the promise must be madeto the offeror; the promise must be consistent with the offer （the promise must be a complete, mere consent to the offer ） ; Commitments must be made within the validity of the offer. If a commitment has a material change in the offer, the offer should be co
18、nsidered to be a new offer.同时山姆提出想要以 3000英镑的价格买萨莉的钢琴，这可以看 成是山姆对萨莉发出的新的要约， 因为它改变之前要约的实质性 内容，所以应当是一个新要约。但是此时萨莉也是立即拒绝了， 所以他们之间的要约失效， 对他们双方没有拘束力。即使两个小 时之后山姆想要以 3500 英镑的价格购买钢琴，萨莉也可以拒绝。 因此，山姆不能要求萨莉以 3500 英镑的价格把钢琴卖给他。At the sametime, Sams proposal to buy Sally3,000 could be seen as Sams new offer to Sally.
19、 Because it changed the substance of the previous offer, it should be a new offer.But at this moment, Sally immediately rejected it, so the offer betwee n them lapsed and they were not bound by both parties.Eve n if Sam wants to buy the pia no for 3500 two hours later,Sally can refuse. Therefore, Sa
20、mcan not ask Sally to sell the piano for 3500.Question 3: If Sam agrees promptly to pay 3,500 rather than trying to pay 3,000 for the piano offered by Sally, does there exist an en forceable con tract betwee n them, why?问题3:如果山姆立即同意了以 3500英镑买萨莉的钢琴而不是以3000英镑的价格，那么他们之间存在一个可强制执行的合同 吗？答案3:存在；An swer 3:
21、There exists an en forceable con tract betwee n them.The reas on is as follows.根据合同法第八条：“依法成立的合同，对当事人具有法律约束力。”“依法成立的合同，受法律保护。Accord ing to Article 8 Bin di ng Effect; Legal Protectio nA lawfully formed con tract is legally bin di ng on the parties.根据合同法第二十三条关于承诺期限的规定： “承诺应当在要约确定的期限内到达要约人。 要约没有规定承诺期限
22、的， 承诺应当依照下列规定到达：（一）要约以对话方式作出的，应当即时作 出承诺，但当事人另有约定的除外。Article 23 Timely Dispatch of Accepta neeAn accepta nee shall reach the offeror with in the periodprescribed in the offer.Where the offer does not prescribe a period for acceptanee, theaccepta nee shall reach the offeror as follows:（i） Where the of
23、fer is made orally, the accepta nee shall bedispatched immediately, uni ess otherwise agreed by theparties;根据合同法第二十五条：“承诺生效时合同成立。Article 25 Con tract Formed upon Effective ness of Accepta neeA eon tract is formed once the accepta nee becomes effective.根据合同法第二十六条：“承诺通知到达要约人时生效。Article 26 Effective ne
24、ss of Accepta neeA no tice of accepta nee becomes effective once it reaches theofferor.第四十四条第一款：“依法成立的合同，自成立起生效。Article 44 Effective ness of Con tractA lawfully formed eon tract becomes effective upon itsformatio n.如果山姆当时立即同意了以 3500英镑的价格买萨莉的钢琴，表示山姆对萨莉发出的要约作出了一个承诺， 由于双方是通过电话沟通的，那么当承诺到达要约人萨莉时承诺生效， 也就是
25、双方之间的合同成立。而且它也符合国家的意志和社会公共利益， 合同生效，对双方当事人具有法律约束力。 那么当然山姆和萨莉之间 存在着一个可强制执行的合同。I f Sam immediately agreed to buy Sally 3500, itmeansSamhad madea promise to Sallys offer and the two sides promised to come into force when they reached a promise. That is to say, the contract between them is established. It also conforms to the will of the state and the public interest. The contract takes effect and is legally binding on them. Of course, there exists an enforceable contract between Sam and Sally.
