展开全部“need”双重角色的用法及其区别
“need”既可以作情态动词，也可以作实义动词，但是它们的用法不同。作为情态动词的“need”的用法与其他情态动词“can”，“may”，“must”的用法基本相同：在限定动词词组中总是位居第一，没有非限定形式，即没有不定式、-ing分词或-ed分词等形式；第三人称单数现在时没有词形变化；情态动词之间是相互排斥的，即在一个限定动词词组中只能有一个情态动词。下面是“need”作为情态动词的用法：
一、need表示“需要”或“必须”，通常用于否定句和疑问句。例如：
1．you needn't do it again．你不需要再做了。2．he needn't worry about it．这件事他无需担心。3．need he do th** homework first？他需要先做这些作业吗？4．need they fill in the form？他们需要填表吗？二、在否定句中，可以用need的否定形式＋不定式完成体。例如：
1．we needn't h**e worried．其实我们不必要慌。2．you needn't h**e mentioned it．你本来不必提起这件事。3．you needn't h**e said that when he asked．当他问的时候，你其实不必要说。三、needn't后的不定式间或也能用进行式或被动语态。例如：
1．he needn't be standing in the rain．他不必要站在雨中。2．we needn't be waiting in th** place．我们不必要在这儿等。3．the hedges needn't be trimmed th**week．本周树蓠不必要整修。“need”作为实义动词时，通常用法是：
人＋need＋to do
物＋need＋doing
物＋need＋to be done
另外，“need”后还可以直接跟名词。请看下面的例子：
1．we need to collect the parcel before we le**e for england．去英国之前，我们需要收拾好行李。2．we need to tell him the truth．我们需要告诉他真相。3．my car needs repairing．我的汽车需要修理。4．the flowers need watering．这些花需要浇水。5．h** leather shoes needs to be mended．他的皮鞋需要修补。6．her room needs cleaning．她的房间需要打扫。7．it ** aquestion that needs very careful consideraton．这是一个需要慎重考虑的问题。回答者：tommylyh-见习魔法师 ** 2-1 17:35
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回答者：qiuxuelx-秀才 二级 2-1 17:35
source:http://zhidao.baidu.com/question/15153880.html?fr=qrl3
n需要,必需 缺乏;穷困;困难;危急[常用复]需要的东西
be in need of food
需要食物
daily needs
日用品=there ** no need to hurry).不用着急。sat**fy one's needs
满足某人的需要
from each according to h** ability,to each according to h** needs
各尽所能,按需分配
needs test
经济情况调查(如对申请救济金的失业人员和年老者的调查)
help people in need
帮助处于困难中的人们
** there any need for you to go there?你有必要去那里吗?she feels the need of companionship.
她感到需要友谊。there ** no need for[of]hurrying
v.
（否定形式略写为 needn't）（常与to连用）需要
plant needs water.
植物需要水。he needed all h** charm to persuade her that it was not h** fault.
他需要使出浑身解数来叫她相信那不是他的错。my shirt needs a button.
我的衬衫需要一枚钮扣。she's on holiday;she needed a change from work.
她正在度假,她需要放下工作改变一下生活。these six kitchens are all needed when the plane ** full of passengers.
这六个厨房在飞机载满旅客时都用得着。you didn't need to tell him the news;it just made him sad.
你无需告诉他这一消息,那只会使他悲哀。必须，不得不
you needn't talk so loud.
你不必这么大声讲话。need you go so soon?你非得这么快就走吗？we need to work harder.
我们必须更加努力工作。you needn't h**e told him the news;he knew it already.
你不必再告诉他这个消息，他已经知道了。n.
缺乏；缺少；需要
children's need for milk
儿童需要牛奶
the hungry children were in need of food.
这些饥饿的孩子需要食物。责任；义务
a need for taxes
纳税的义务
no need to go yet,it's still early.
不必走，还早着呢。必需品
their need was fresh water.
他们所必需的是淡水。贫穷；困难
illness,need,and other troubles of the world
疾病、贫困以及世界上其他的烦恼
he ** in great need.
他穷得很。need
[ni:d]
n.
需要,必需,必需品,要求,贫困
vt.
需要
modal v.必要,必须
need
need
ahd:[n¶d]
d.j.[ni8d]
k.k.[nid]
n.（名词）
a lack of something required or desirable:
需要：对想要或期望的事物的缺乏：
crops in need of water;a need for affection.
需要水的庄稼；对感情的需要
something required or wanted;a requ**ite:
必需品：要求或需要的事物；需要物：
our needs are modest.
我们的必需品是谦虚
necessity;obligation:
必要；义务：
there ** no need for you to go.
你没有必要去
a condition of poverty or m**fortune:
贫困：贫穷或不幸的状况：
the family ** in dire need.
这个家庭极为贫困
v.（动词）
need.ed，need.ing，needs
aux.（助词）
to be under the necessity of or the obligation to:
必须要：必须要，有义务要：
they need not come.
他们不必来
v.tr.（及物动词）
to h**e need of;require:
需要；想要：
the family needs money.
这个家庭需要钱
v.intr.（不及物动词）
to be in need or want.
需要，想要
to be necessary.
有必要
middle nede
中古英语 nede
from old n¶¶d}[d**tress,necessity]
源自 古英语 n¶¶d}[穷困，贫困]
need，necessity，exigency，requ**ite
these nouns denote a condition in which something essential ** required or wanted;they also refer to that which ** required or wanted.
这些名词都指处于对必需品的要求和需求的一种状况；它们也指需要的或要求的东西。need ** the most general:
need 最普遍：
there's no need to be concerned.
没必要担忧。she ** serene and contented;她很安详、平静；her emotional and spiritual needs are being met.
她感情和精神上的需要都得到了满足。necessity strongly than need suggests urgency,inevitability,or un**oidable obligation:
necessity 比need 更强，用来指紧迫的、不可避免的或不可躲避的义务：
“i think the necessity of being ready increases.—look to it”(abraham lincoln).
“我认为做好准备的 紧迫性增加了。注意”（亚伯拉罕·林肯）。“the rehabilitation of the cabin became a necessity”(bret harte).
“小屋的重新修建已是不可避免的了”（布雷特·哈特）。exigency implies acute urgency,especially that ar**ing from conditions or circumstances such as those of an emergency:
exigency 指非常紧迫，尤指产生于类似紧急事件的条件或环境：
“no.more pernicious[doctrine]was ever invented.than that any of[the constitution's]prov**ions can be suspended during any of the great exigencies of **”(d**id d****)
“没有…曾经创造的 能比在一次**的危急关头对 条款的取消更为有害的”（大卫·戴维斯）。requ**ite applies to something ind**pensable:
requ**ite 指不可缺少的事物：
“a place where the three grand requ**ites of water,fuel and fodder were to be obtained”(james fenimore cooper).see also synonyms at lack
“三种主要必需品，水、燃料和草料都具备的地方”（吉姆斯·费尼莫尔·库珀）参见同义词 lack
depending on the sense,the verb need beh**es sometimes like an auxiliary verb(such as can or may)and sometimes like a main verb(such as want or try).when used as a main verb,need agrees with its subject,takes to before the verb following it,and combines with do in questions,negations,and certain other constructions:
根据语义，动词need 有时当作助动词来使用（如 can 或 may)，有时象实义动词（如want 或 try)。当用作实义动词时，need 和主语一致，把to 放在其后面动词的前面，在疑问句、否定句或某些特定的造句法上和do 连用：
he needs to go.
他想走。does he need to go so soon?他这么快就要走吗?he doesn't need to go.
他不需要走。when used as an auxiliary verb,need does not agree with its subject,does not take to before the verb following it,and does not combine with do:
当用作助动词时，need 不用和主语一致，不用把to 放在其后动词的前面，并且不用和do 连用：
he needn't go.
他不必走。need he go so soon?他这么快就要走吗?the auxiliary forms of need are used primarily in present-tense questions,negations,and conditional clauses.they differ subtly in meaning from the main verb forms in that they always refer to an externally imposed obligation.hence one might say you needn't(or less formally,don't need to)fill out both forms,but where the sense of necessity ** internal to the subject,only the main verb can be used:
need 的助动词形式主要用于现在时态的疑问句、否定句和条件句中。它们在意思上和用作实义动词的形式有细微的区别，它们总指外部加强的压力。因此我们可以说你没必要（或不太正规的 don't need to)填两份表格，但是对于物体来说需要的意思是内在的，所以只能用实义动词：
i don't need to(not needn't)be told how to manage my own affairs.
我不需要（而不是 needn't)被告诉怎知管理自己的事情。note also that the use of need as an auxiliary ** often accompanied by a presupposition that the activity inquestion has in fact been performed.the boys needn't h**e spoken frankly implies that they did in fact speak frankly,whereas the sentence the boys did not need to speak frankly does not;only the latter could be followed by a clause like they conveyed their meanings by indirection.
还需注意need 用作助动词时经常伴随一个先决条件，质问的动作事实上已经完成了。那些男孩们本来不需要坦诚相告的 意味着他们事实上已经坦率地说了，然而这个句子男孩们不需要坦诚地说话 就没有这个意思；只有后者可以在其后跟这样一个句子，如他们间接地表达他们的意思
need
[ni:d]
v.
（否定形式略写为 needn't）（常与to连用）
需要
plant needs water.
植物需要水。he needed all h** charm to persuade her that it was not h** fault.
他需要使出浑身解数来叫她相信那不是他的错。my shirt needs a button.
我的衬衫需要一枚钮扣。she's on holiday;she needed a change from work.
她正在度假,她需要放下工作改变一下生活。these six kitchens are all needed when the plane ** full of passengers.
这六个厨房在飞机载满旅客时都用得着。you didn't need to tell him the news;it just made him sad.
你无需告诉他这一消息,那只会使他悲哀。必须，不得不
you needn't talk so loud.
你不必这么大声讲话。need you go so soon?你非得这么快就走吗？we need to work harder.
我们必须更加努力工作。you needn't h**e told him the news;he knew it already.
你不必再告诉他这个消息，他已经知道了。need
n.
缺乏；缺少；需要
children's need for milk
儿童需要...