require、demand、request、claim都可以表示要求,而且是核心考点，经常出现再大大小小的考试中……
require--一般表示因需要而要求（通常不用于进行时）
to need something or make something necessary
需要；有赖于；要求；规定
[VN] These pets require a lot of care and attention.
这些宠物需要悉心照顾。
This condition requires urgent treatment.
这种情况得紧急处理。
Do you require anything else? (= in a shop/store, for example)
你还需要什么吗？
[VN to inf] True marriage requires us to show trust and loyalty.
真正的婚姻有赖于我们表现出信任与忠诚。
[V that] The situation required that he be present.
这种情形需要他在场。
(BrE also) The situation required that he should be present.
这种情形需要他在场。
以上2句是虚拟语气用法。
[V -ing] Lentils do not require soaking before cooking.
小扁豆在烹饪前不必浸泡。
The rules also require employers to provide safety training.
这些规定也要求雇主们提供安全训练。
What clause do you require in the contract?
你要求在合同中订上什么条款?
to make sb do or have sth, especially because it is necessary according to a particular law or set of rules
使做（某事）；使拥有（某物）；（尤指根据法规）规定
require sth (of sb)
What exactly is required of a receptionist ？接待员的职责到底是什么？
The wearing of seat belts is required by law.
法律规定必须系安全带。
‘Hamlet’ is required reading (= must be read) for this course.
《哈姆雷特》是这门课程的指定读物。
Several students failed to reach the required standard.
有几名学生没有达到规定的标准。
[VN to inf] All candidates will be required to take a short test.
所有候选者都要参加一次小测验。
Legislation will require UK petrol companies to meet an EU specification for petrol.
法规将要求英国的汽油公司必须达到欧盟对汽油的规格要求。
《柯林斯高阶英汉双解学习词典》
It did not require a great deal of perception to realise the interview was over.
并不需要多少洞察力也能意识到面试已经结束了。
《柯林斯高阶英汉双解学习词典》
It'll require indomitable will to accomplish the task.
完成这项工作需要百折不回的毅力。
《汉英大词典》
You will need to give the dates you wish to stay and the number of rooms
you require.
需要提供想要入住的起止日期以及所需的房间数目。
Buyers might require further assurances before parting with their cash
买方在付现之前可能要求提供进一步的担保。
You may have free passage across our territory whenever you require it.
无论你什么时候需要，都可以自由穿过我们的领地。
You will need to give the dates you wish to stay and the number of rooms you
require.
需要提供想要入住的起止日期以及所需的房间数目。
Girls do better on open-ended tasks that require them to think for themselves.
女孩子更擅长做需要独立思考的开放式任务。
《柯林斯高阶英汉双解学习词典》
demand
作动词，表示：to ask for something forcefully, in a way that shows that you do not expect to be refused 坚决请求，强烈要求；强要；指强烈要求、坚决要求：（尤指困难、使人劳累、令人烦恼等的）要求
She demanded an immediate explanation.
她强烈要求立即作出解释。
Mr Byers last night demanded an immediate explanation from the Education Secretary
昨晚拜尔斯先生要求教育大臣立刻作出解释。
He said the task of reconstruction would demand much patience, hard work and sacrifice
他说重建任务将需要付出极大的耐心、艰辛和牺牲。
I demanded an explanation.
我要求给我一个解释。
The union is demanding a seven percent pay rise this year.
汽车工会要求今年加薪7%。
He has always demanded the highest standards of behaviour from his children.
他总是以最高的行为准则来要求自己的孩子。
[ + speech ] "And where do you think you're going?" demanded the police officer.
“你觉得自己在朝哪里走？”警察问道。
[ + to infinitive ] I demand to see the manager.
我要求见经理。
[ + that ] She demanded that he return the books he borrowed from her.
她要求他把从她那里借走的书还回来。
Russia demanded that Unita send a delegation to the peace talks
俄罗斯要求安盟派代表团参加和谈。
《柯林斯高阶英汉双解学习词典》
They are demanding that all troops should be withdrawn.
他们强烈要求所有部队撤离。
The UN has demanded that all troops be withdrawn.
联合国已要求撤出所有部队。
（should可以省略）
作名词：表示困难的要求（尤指困难、使人劳累、令人烦恼，巨大等的）
His new job makes a lot of demands on him (= he has to work very hard).
新工作对他要求很高。
It is self-evident that we will never have enough resources to meet the demand
不言而喻，我们永远都不会有足够的资源来满足需求。
This has forced airlines to discount fares heavily in order to spur demand
这迫使航空公司对机票大幅打折来刺激需求。
The supply exceeds the demand.
供过于求。
The rate of growth of GNP will depend upon the rate of growth of aggregatedemand
国民生产总值的增长率将取决于总需求的增长率。
Supply and demand on the currency market will generally balance.
货币市场上的供求将大致持平。
《柯林斯高阶英汉双解学习词典》
request
the act of politely or officially asking for something
（礼貌、正式的）要求，请求
They received hundreds of requests for more information.
数以百计的人要求他们提供更多的信息。
You will do as I request, if you please
请按我的要求做。
《柯林斯高阶英汉双解学习词典》
[VN She requested permission to film at the White House.
她申请准予在白宫拍摄。
Mr Dennis said he had requested access to a telephone
丹尼斯先生说他已经请求使用电话。
You can request a free copy of the leaflet.
你可以索要一份免费的宣传单。
[ + to infinitive ] The boss refused our request to leave work early.
老板拒绝了我们早下班的请求。
The clause was added to the contract at Carlos's request (= because Carlos asked for this).
这一条款是在卡洛斯的要求下添加到合同中的。
They requested him to leave
他们要求他离开。
Students are requested to park at the rear of the Department.
学生必须把车停在该系后面。
We were requested to assemble in the lobby.
要求我们在大厅集合。
You are requested not to smoke in the restaurant.
请不要在餐馆里吸烟。
[V that] She requested that no one be told of her decision until the next meeting.
她要求下次开会前不要向任何人透露她的决定。
She requested that no one should be told of her decision.
她要求不要向任何人谈起她的决定。
She had requested that the door to her room be left open.
她要求不要关闭通向她房间的门。
《柯林斯高阶英汉双解学习词典》
Vietnam made an official request that the meeting be postponed.
越南已经正式请求将会议推迟。
（可以省略should）
也可以名词：
The request was gracefully refused.
这个请求被有礼貌地回绝了。
A United Nations spokeswoman in New York said the request would be considered.
联合国的一名女发言人在纽约说，该要求会得到考虑。
《柯林斯高阶英汉双解学习词典》
He came at my request.
他应我的请求而来。
《汉英大词典》
That country made an urgent request for international aid after the tsunami happened.海啸发生后，该国紧急请求提供国际援助。
The opposition leader repeated his request that they release the election results as soon as possible.反对党领导人再次要求他们尽快公布选举结果。
claim
to ask for something of value because you think it belongs to you or because you think you have a right to it 要求（拥有）；认领；索取，索 要（
多指因有权得到某事物而公开提出要求。）宣称;声称;断言;要求(拥有);索取;认领;索要
Most of those who claimed asylum were refugees.
那些申请政治避难者大多数都是难民。
The bank claimed payment from Susan.
银行要求苏珊付款。
They claim the council has prejudiced their health by failing to deal with asbestos.
他们声称，理事会没有处理好石棉的问题，从而损害了他们的健康。
They claimed losses from the express company.
他们就这次损失向那家快递公司提出赔偿要求。
The police said that if no one claims the watch, you can keep it.
警方说如果没人认领这块表，你可以留着它。
When King Richard III died, Henry VII claimed the English throne.
理查德三世去世后，亨利七世要求继承英格兰王位。
He claims (that) he was not given a fair hearing.
他声称他未得到公正的申述机会。
He claimed that it was all a conspiracy against him
他声称这一切都是一场针对他的阴谋。
He repeated his claim that the people of Trinidad and Tobago backed his action
他再次声称，特立尼达和多巴哥的人民支持他的行动。
The civil war claimed the life of a U.N. interpreter yesterday
昨天，内战夺去了一位联合国译员的生命。
I don't claim to be an expert.
我不敢自称为专家。
A man claiming to be a journalist threatened to reveal details about her private life
一个自称是记者的人威胁要公开有关她的私生活的细节。
He can claim to have been defeated by opponents copying his own tactics.
他可以说是被仿效自己策略的对手们给打败了。
《柯林斯高阶英汉双解学习词典》
Scientists are claiming a major breakthrough in the fight against cancer.
科学家们宣称攻克癌症已有重大的突破。
It was claimed that some doctors were working 80 hours a week.
据说有些医生每周工作80小时。
insist
to demand that sth happens or that sb agrees to do sth 指坚决要求、坚持：
I didn't want to go but he insisted.
我并不想去，但他硬要我去。
We insist on the highest standards at all times.
我们始终坚持最高标准。
expect
to demand that sb should do, have or be sth, especially because it is their duty or responsibility 指要求、认为应得、指望，尤因义务或责任：
I expect to be paid promptly for the work.
我要求即时付工钱。
ask不如demand和expect语气强烈，demand和expect更像命令。
你对他要求过分了。