Contract、treaty、convention、understanding与accord都有“协定，协议，契约，合同”之意，但是表示的这些合同有所不同，以下做具体介绍。

Contract是我们在日常和法律文本中都经常见到的表示合同的词汇，该词强调指指双方或多方订立的【具有法律效力的正式的书面合同或契约】。如：to enter into/make/sign a contract签订合同，a contract of employment 雇用合同，a research contract 从事研究的合同，breach of contract 违约。

Treaty一词常强调指【（国家之间的）条约，协定】。the Treaty of Rome 《罗马条约》，a peace treaty 和平协定，to draw up/sign/ratify a treaty 起草╱签署╱正式批准条约，the Treaty of Rome, which established the European Community

建立了欧洲共同体的《罗马条约》。

Convention同treaty相近，常常指【（国家或首脑间的）公约，协定，协议】。如the Geneva convention日内瓦公约，the United Nations convention on the rights of the child联合国儿童权利公约。

Accord同Treaty相近，常指【国际间的正式协议】。

Understanding则指【非正式的协议】，常指人们之间的口头约定，不具约束力。如：We had not set a date for marriage but there was an understanding between us.我们还没有确定结婚日期，不过我们已有了一致意见。memorandum of understanding 谅解备忘录，指处理较小事项方面的条约。

参考双语例句：

①The assessments will be recorded in the administrative “check-list”, used to confirm that the contract has been drawn up in accordance with the prevailing rules and procedures, and which must be completed before final payment of a contract can be authorized.

评估结果将记入行政“检查单”，用于确认合同起草工作符合主要的规则和程序，这必须在合同最后付款获得批准前完成。

②As the Council’s meeting addresses the issue of nuclear-weapon-free zones, NAM reaffirms the need for the speedy establishment of a nuclear-weapon-free zone in the Middle East in accordance with Security Council resolution 487 (1981) and paragraph 14 of Council resolution 687 (1991) and the relevant General Assembly resolutions adopted by consensus; and, pending its establishment, NAM demands that Israel, the only country in the region that has not joined the Treaty on the Non-Proliferation of Nuclear Weapons or declared its intention to do so, renounce possession of nuclear weapons, accede to the Treaty without further delay, place promptly all its nuclear facilities under International Atomic Energy Agency full scope safeguards according to Security Council resolution 487 (1981) and conduct its nuclear-related activities in conformity with the non-proliferation regime.

因为安理会这次会议将审议无核武器区问题，不结盟运动重申必须根据安全理事会第487(1981)号决议和安理会第687(1991)号决议第14段以及协商一致通过的大会相关决议，加速建立中东无核武器区；在此之前，不结盟运动要求该地区唯一未加入、并且也未宣布打算加入《不扩散核武器条约》的国家以色列放弃拥有核武器，毫不拖延地加入该条约，并根据安全理事会第487(1981)号决议，迅速将其所有核设施置于国际原子能机构的全面保障监督之下，同时依照不扩散机制的要求开展与核有关的活动。

③This legislation provides for universal jurisdiction over any or a combination of the following: (a) grave breaches of the Geneva Conventions and Additional Protocol I thereto (primarily States members of the Commonwealth); (b) crimes specified under the Second Protocol to the 1954 Hague Convention and the International Convention for the Protection of All Persons from Enforced Disappearance (for example, Cyprus, Japan and the Netherlands); (c) other violations of international humanitarian law where no treaty requires universal jurisdiction, such as war crimes committed in non-international armed conflict (Belgium, Canada, New Zealand and the Philippines) and violations of treaties that either prohibit or regulate the use of certain weapons (South Africa); (d) the war crimes list contained in article 8 of the Rome Statute (Belgium, Canada, Germany, New Zealand and the United Kingdom).

这种立法为以下任何罪行或罪行组合规定了普遍管辖权：(a)严重违反日内瓦四公约及其《第一附加议定书》的行为(主要是英联邦成员国)；(b)1954年《海牙公约》《第二号议定书》和《保护所有人免遭强迫失踪国际公约》特别规定的犯罪(例如塞浦路斯、日本和荷兰)；(c)没有条约规定普遍管辖权的其他违反国际人道主义法行为，如在非国际武装冲突中实施的战争罪(比利时、加拿大、新西兰和菲律宾)以及违反禁止或管制使用某种武器的行为(南非)；(d)《罗马规约》第 8 条所列的战争罪(比利时、加拿大、德国、新西兰和联合王国)。

④This resulting realignment is fully in line with the overall mandate of ECA to promote the economic and social development of Africa and also responds well to other relevant mandates at the global and regional levels, such as the Copenhagen Accord, the Outcome of the Conference on the World Financial and Economic Crisis and Its Impact on Development, and the outcomes of the 2009 ECA Conference of African Ministers of Finance, Planning and Economic Development.

这样的调整完全符合非洲经委会促进非洲经济和社会发展的总任务，也很好地反应了其他全球和区域各级有关任务，如《哥本哈根协议》、世界金融和经济危机及其对发展的影响问题会议成果以及2009 年非洲经委会非洲财政、规划和经济发展部长会议的成果。

⑤Several State agencies signed a memorandum of understanding with the Office, thus establishing an effective system of cooperation and consultation.

几个国家机构与公众保护办事处签订了一个谅解备忘录，从而建立了一个有效的合作与协商系统。