【奇速英语】点拨英语词汇dozen的用法
【知识学习】高考英语单元知识点复习Unit 20
高考英语单元知识点复习Unit 20Unit20理解:要点诠释单词.dozen讲：n.十二；打例:Givemeadozen,please.请给我来一打。
onlyabouthalfadozenturnedup.只有六七个人到了。
HeboughtthreedozenredrosesforheronValentine’sDay.在情人节他给她买了三打红玫瑰。
链接•提示dozen作“十二”讲，其前有数词或a,few,several,many 等词修饰时，用单数形式；若后面接代词时，dozen后of不能省略。
a,few,several,many修饰dozen其后of可有可无。
类似单词还有score,handred,thousand,million。
dozensof许多；scoresof许多。
练:Applesareusuallysoldby_________weight,andeggsare sometimessoldby____________dozen.A.the;theB./;ac./;theD.the;a提示:本题看似考查冠词，实际上考查固定搭配:byweight意为“按重量；bythedozen意为“论打”。
答案:c2.spare讲：v.抽出；拔出；留出；匀出；省得；免得；饶恕；赦免；放过adj.空闲的；多余的；备用的n.备用品例:I’dlovetohavearest,butIcan’tsparethetimejustnow.我想休息一下，但眼下找不出时间。
wecanonlyspareoneroomforyou.我们只能给你腾出一个房间。
Hewantedtosparehismotheranyanxiety.他不想让母亲有丝毫的担忧。
Duringthebombingonlyonehousewasspared.在轰炸中，只有一座房子幸免。
I’mafraidIhaven’tgotanysparecash.恐怕我手头没有闲钱。
高考英语单元知识学习总结要点考试复习学习要点Unit 20
高考英语单元知识点复习Unit 20Unit20理解:要点诠释单词.dozen讲：n.十二；打例:Givemeadozen,please.请给我来一打。
onlyabouthalfadozenturnedup.只有六七个人到了。
HeboughtthreedozenredrosesforheronValentine’sDay.在情人节他给她买了三打红玫瑰。
链接•提示dozen作“十二”讲，其前有数词或a,few,several,many 等词修饰时，用单数形式；若后面接代词时，dozen后of不能省略。
a,few,several,many修饰dozen其后of可有可无。
类似单词还有score,handred,thousand,million。
dozensof许多；scoresof许多。
练:Applesareusuallysoldby_________weight,andeggsare sometimessoldby____________dozen.A.the;theB./;ac./;theD.the;a提示:本题看似考查冠词，实际上考查固定搭配:byweight意为“按重量；bythedozen意为“论打”。
答案:c2.spare讲：v.抽出；拔出；留出；匀出；省得；免得；饶恕；赦免；放过adj.空闲的；多余的；备用的n.备用品例:I’dlovetohavearest,butIcan’tsparethetimejustnow.我想休息一下，但眼下找不出时间。
wecanonlyspareoneroomforyou.我们只能给你腾出一个房间。
Hewantedtosparehismotheranyanxiety.他不想让母亲有丝毫的担忧。
Duringthebombingonlyonehousewasspared.在轰炸中，只有一座房子幸免。
I’mafraidIhaven’tgotanysparecash.恐怕我手头没有闲钱。
高考英语近三年真题语法精讲精练专题10数词和主谓一致
语法专题十 数词和主谓一致一、数词数词分为两种：基数词(表示数目)和序数词(表示顺序)。
考点一 dozen与score的用法1．dozen (一打，十二)，score (二十)与具体数词或与many，several 等连用时，后不加s，所修饰的名词前常省去of。
如：two dozen eggs 两打鸡蛋，many dozen pencils好多打铅笔；dozen，score 的复数形式后接of时，表示“许多”，是概数。
如：dozens of eggs几十个鸡蛋，scores of pencils几十支铅笔。
此外，有“数词＋score ＋of＋名词”这种用法。
如：two score of eggs 40个鸡蛋，three score of people 60个人。
2．当所修饰的名词之前有限定词these，those，my，your等或是修饰人称代词宾格them，us，you时，这时需要加of。
如：two dozen of these pens，three score of them。
考点二 分数的表达法分子用基数词，分母用序数词，若分子大于1，则分母用复数。
如：onefourth(a quarter) 1/4twofifths 2/5Twothirds of the money was spent on food.考点三 年龄的表达法表示某人的确切年龄，用“基数词＋years old”或者“at the age of＋基数词”，也可直接用基数词；表示某人几十多岁时，用“in one's＋逢十的基数词的复数(如tens，twenties，thirties等)”来表达。
She is still in her twenties.她才二十几岁。
考点四 年代的表达法表示“几十年代”时，在阿拉伯数字后加s或's。
My grandpa was born in 1910's.二、主谓一致谓语动词的数必须和主语的人称和数保持一致，这就叫主谓一致。
初一上册英语期中复习要点之助动词do,dose用法
初一上册英语期中复习要点之助动词do,dose用法
精选初一上册英语期中复习要点之助动词do,dose用法
助动词(do,does)的'用法
只有实意动词作谓语时才涉及使用助动词。
以like为例：1)当句子为肯定句时不涉及使用助动词，只涉及“主谓一致”原则。
eg:IlikeEnglishalot.MichaellikesChinesefoodverymuch.
2)当句子为否定句时，要根据主语的人称来决定使用相应的助动词：当主语为“三单”时，要使用does;当主语为“非三单”时，用助动词原形do。
例如把下列句子变否定句：Kangkanglikesmath.----Kangkangdoesn'tlikemath.
Theylikesports.------Theydon'tlikesports.
3)当句子变疑问句时，同样要根据句子的主语来决定在句首使用Do或Does.例如下列句子变问句：
MichaellikesChineseFood.----DoesMichaellikeChinesefood?Yes,hedoes./No,hedoesn't.(主语是第三人称单数，变疑问句时，助动词用三单形式，谓语动词用原形) JaneandHelenlikemusic.----DoJandandHelenlikemusic?Yes,theydo./No,theydon't.
【精选初一上册英语期中复习要点之助动词do,dose用法】。
score 与dozen
score 与dozen■崔长平河南遂平一高（463100）■score 意为“廿，二十”，其前有数词修饰限制时，score词尾不加s，表示复数概念。
但在scores of …短语中须使用复数形式。
a score of …意为“二十个……”或“大量的……”。
scores of …意为“许多的……，大量的……”，不表示具体数目。
A score of people were present at the party.Scores of people attended the special meeting last night.表示具体数目：three score and ten(students) 七十个（学生）two score (of) eggs 四十个鸡蛋three score (of) workers 六十个工人four score (of) visitors 八十个观光者（作定语时，score后面一般都加有of，但of也可省略。
）■dozen意为“十二个，一打”，其前有数词或者具有数词意义的词（如：many，several，some等）修饰限制时，不能使用复数形式，但在短语dozens of…（几十个，许多个）中须用复数形式。
dozen用作单数时，其后一般不能加of，dozens of…中的of不能省去。
Three dozen sheets of paper are enough for me.They sold three dozen copies of the magazines today.Dozens of children were there before us.但若表示“部分与整体”的关系时，dozen即使是单数形式，也须加of，这时of后面多是一个加有限定词（如：these，those，the，my，Tom′s 等）的复数名词或代词。
He bought three dozen eggs yesterday. 他昨天买了三打鸡蛋。
英语零基础语法数词
1. once 一次single 单一的singleness 单一；单身single-handed 独手的，只用一只手的2. pair 双，对double 两倍的double-decker 双层床；双层电车double-chinned 双下巴的3. quarter 四分之一；一刻钟；两角五分钱（美国、加拿大的）three quarters 四分之三4. dozen 十二，一打two dozen of 两打……dozens of 好几打，很多的in dozens 成打的dozenth = twelfth 第十二a baker's (/ printer's / long) dozen 十三个（baker's dozen的来源：起初面包师在制作面包时偷工减料，克扣份量。
这种做法弄得民怨沸腾，最后官方不得不专门为面包师们制订了投料标准，凡达不到标准的就要受到处罚。
为了避免被罚，面包师们就在出售面包时每打多给一个，即十三个为一打。
）5. score 二十three score and ten 七十two score of 四十个……scores of 大批的in scores 大量地，大批地6. fortnight 十四日，两星期fortnightly 两星期一次的；双周刊7. decade 十年century 百年，世纪bicentenary 二百周年（的）octocentenary 八百周年（的）millenary / millennium 千年，千年期基数词和它的修饰语一、注意基数词与其他词连用时的位置关系：The first two years have been very successful.开头两年非常成功。
Look at the three young men.看那三个年轻人。
These are for my two daughters.这些是给我那两个女儿的。
Any two people will do.任何两个人都可以。
many和alot,英语量词你会用吗？
many和alot,英语量词你会用吗？比如前些天，一位用户问的“a dozen", 还有"a ton", "a bunch"......今天我们就总结这些常用量词！中英文量词的区别measure word: 量词Chinese meansure words are very specific, i.e. many can be only used to describe a certain type of thing: 中文的量词比较特定，不同的量词对应不同的东西Measure words in English aren't as specific as Chinese: 英语的量词没有中文那么特定But because they're more general, using them appropriately might be challenging: 但是因为比较宽泛，所以要恰当使用也不那么容易美国人最爱用的量词：a dozenA dozen: 一打A dozen means 12:一打表示12个Eggs are most commonly bought by the dozen: 最常用来形容鸡蛋▪A dozen eggs: 一盒鸡蛋We wouldn't call it a box of eggs: 英语里不会说一盒蛋，而是说一打鸡蛋You can also buy half a dozen eggs: 也可以买小盒的，半打Half a dozen or a half dozen?Both are correct: 两种说法都是正确的Dozens can also be used in the plural form: 打还可以变成复数▪Dozens of people: 好多人（几十个)▪Dozens of options: 许多的选择Dozens究竟是多少？Since English doesn't really have a word for "tens", dozens is used to express the idea:由于英语没有一个词表明“几十”，所以dozens用来形容几十这个数量"Doze ns" is the next step down from hundreds: “dozens”代表几十个，再上去就是几百个最浪漫的量词：a couple现在常说的“CP", 就是couple. 不过美国人可不会说“CP", 这是有亚洲特色的英语。
Unit+6+课件+2023-2024学年仁爱版九年级英语下册
考点精讲 考点1 I would rather watch sports shows than those ones. 比起那些节目我更愿意看体育节目。 would rather do A than do B=prefer to do A (rather) than do B I would rather go with you than stay at home alone. 我宁愿和你一起走,也不愿独自一人在家里。
—Oh, they were put under the table.
A.dozen
B.dozen of
C.dozens of
考点3 Now we have to learn to do with television programs, too. 现在我们也必须学会选择电视节目了。 do with 处理;放置 What are you going to do with that vase? 你要怎么处理那个花瓶? deal with 处理,对付 She is good at dealing with stress. 她善于应付压力。 do with常与what连用,deal with常与how连用。
He graduated from York University with a degree in Psychology. 他毕业于约克大学,获心理学学位。 He is a graduate in medicine. 他是医科毕业生。
考点7 He is still alive after a bad accident. 他在一次严重的事故后仍然活着。
lively adj.活泼的;活跃的;热烈的 He told a lively story about his life in Africa. 他讲述了一个关于他在非洲生活的生动故事。
dozen, score, hundred用法区别
dozen, score, hundred等词的用法Mr. Smith_______me to buy several_____ eggs for the dinner party.A. asked…dozenB. suggested…dozens ofC. had…dozenD. persuaded…dozenShortly after the accident, two police were sent to the spot to keep order.A.dozen ofB. dozensC.dozenD. dozens of (MET’92)这两道题均选自高考题,都有一定的难度，原因在于dozen，score等词在中学英语中复现率不高,用法又很复杂，一般语法书和词典说明又过于简单。
为此，我们特写本文见它们的用法特点作一归纳。
—49—1.在与不定冠词连用时，dozen等词后面常省略of，直接跟名词:若是人称代词，或名词前有指示词和物主代词(如:these，our等),则不能省略of。
例如：a dozen peoplea dozen sheets of paperHe had come half a dozen times to call upon his sister. 他来看望他姐姐已有六七次了。
You cannot enjoy a story if you stop half a dozen times on every page in order to look up words in the dictionary.I cannot give you a hundred reasons for not going. 我可以给你列出一百条不去的理由。
a dozen of usa dozen of those applesa dozen of your eggsbe six of one and half a dozen of the other 半斤八两；差不多下面是没有省略of 的用法：a score of eggs 二十只鸡蛋a score of people 二十个人a score of reasons 种种理由2．Dozen，score，hundred等词前面有数词修饰时，一般不用复数。
dozen, score, hundred用法区别
dozen, score, hundred等词的用法Mr. Smith_______me to buy several_____ eggs for the dinner party.A. asked…dozenB. suggested…dozens ofC. had…dozenD. persuaded…dozenShortly after the accident, two police were sent to the spot to keep order.A.dozen ofB. dozensC.dozenD. dozens of (MET’92)这两道题均选自高考题,都有一定的难度，原因在于dozen，score等词在中学英语中复现率不高,用法又很复杂，一般语法书和词典说明又过于简单。
为此，我们特写本文见它们的用法特点作一归纳。
—49—1.在与不定冠词连用时，dozen等词后面常省略of，直接跟名词:若是人称代词，或名词前有指示词和物主代词(如:these，our等),则不能省略of。
例如：a dozen peoplea dozen sheets of paperHe had come half a dozen times to call upon his sister. 他来看望他姐姐已有六七次了。
You cannot enjoy a story if you stop half a dozen times on every page in order to look up words in the dictionary.I cannot give you a hundred reasons for not going. 我可以给你列出一百条不去的理由。
a dozen of usa dozen of those applesa dozen of your eggsbe six of one and half a dozen of the other 半斤八两；差不多下面是没有省略of 的用法：a score of eggs 二十只鸡蛋a score of people 二十个人a score of reasons 种种理由2．Dozen，score，hundred等词前面有数词修饰时，一般不用复数。
2017届高考外研版英语二轮复习：语法专题5 数词和主谓一致
考点一 考点二 考点三 考点四 考点五 考点六 考点七
考点五“名词(或代词)+of+名词”做主语时 的主谓一致 1.由“some,plenty,a lot,lots,most,the rest,all,half,part或分数、百分数 +of+名词”等短语做主语时,谓语动词常与of后的名词保持数的一 致。如果of后面所接名词为复数形式,谓语动词用复数形式;如果of 后面所接名词为单数或不可数名词,谓语动词就用单数形式。
2.由and连接的两个或两个以上的单数名词做主语,前面由不定代 词every/each/no修饰时。
Each boy and(each) girl has an apple. 每个男孩和每个女孩都有一个苹果。
3.and连接的两个词是指同一个人、同一事物或同一概念,且两个 名词共用一个冠词时。
(2014江西师大附中期中)A teacher of English and class teacher is
语法专题五 数词和主谓一致
语法专题五 数词和主谓一致
语法专题突破
核心考点
对应演练
-2-
一二
考点一 考点二 考点三 考点四
一、数词 数词分为两种:基数词(表示数目)和序数词(表示顺序)。 考点一dozen与score的用法 1.dozen(一打,十二),score(二十)与具体数词或与many,several 等连 用时,后不加-s,所修饰的名词前介词of有无均可。但是习惯上score 多与of连用,而dozen很少与of连用。如:two dozen eggs 两打鸡 蛋,many dozen pencils好多打铅笔;two score of eggs 40个鸡蛋;three score of people 60个人。dozen,score的复数形式后接of时,表示“许 多”。如:dozens of eggs几十个鸡蛋,scores of pencils几十支铅笔。 2.当所修饰的名词之前有限定词these,those,my,your等或是修饰 人称代词宾格them,us,you时,这时需要加of。如:two dozen of these pens,three score of them。
dozens of 英文解释
DOZENSDozens refer to a quantity of twelve or multiples of twelve. In various contexts, the term “dozens” is used to identify a significant number or a specific grouping of items or entities. It could refer to a set of twelve similar objects or actions. Let’s explore some examples and implications of the term “dozens.”1.Baking: In baking, the concept of dozens is often encountered. Recipesmight call for ingredients to be measured in dozens, such as a dozen eggs or a dozen cookies. Furthermore, baking trays are typically designed to fit a dozen standard-sized cupcakes or muffins.2.Shopping: When purchasing items in bulk, particularly perishablegoods, they are sometimes packaged and sold in dozens. This practice iscommonly seen in the sale of eggs, where cartons of twelve are the standardunit. Similarly, baked goods like bagels or donuts are often sold and packaged in dozens.3.Quantities: Dozens can be used to indicate an approximate quantitywhile remaining somewhat ambiguous. For example, when estimating acrowd’s size, one might say that there were dozens of people present. Itindicates more than just a few individuals without specifying the exact number.4.Mathematical Operations: In mathematical operations, dozens canprovide more variety and ease of calculation. For instance, a baker may have a recipe that needs to be scaled up or down, but maintaining measurements in dozens can simplify the adjustment process. Similarly, rounding off to thenearest dozen can be useful in certain scenarios.5.Expressing Abundance: Using dozens can imply an abundance ofsomething. For instance, saying “there are dozens of options” suggests a wide range of choices or possibilities. It emphasizes the ample availability or variety of a particular item or situation.6.Crafts and DIY: In craft projects or do-it-yourself activities, dozens canrepresent the number of supplies needed. Whethe r it’s a dozen buttons, a dozen beads, or a dozen paintbrushes, this quantity provides a convenient way tomeasure and plan for materials.7.Counting and Grouping: The concept of dozens can aid in counting orforming groups. When organizing items, packing boxes, or distributing items, using dozens can simplify the process. For example, counting items in bundles of twelve can make it easier when organizing large quantities.8.Idiom: The phrase “a dime a dozen” is a commonly used idiom. Itmeans that something is abundant, cheap, or easily obtained. The phrasesuggests that the value or rarity of the item in question is low due to itswidespread availability.In conclusion, “dozens” refers to a quantity of twelve or multiples thereof. It finds application in various fields, including baking, shopping, mathematics, crafts, and expressing abundance. Whether used as a specific measurement, an approximation, or a tool for organization, dozens provide a versatile and practical way to quantify and describe quantities.。
Dozen的用法
Dozen的用法: 请先看下面一道试题：We already have _________ pencils, but we need two _________ pens. A. dozen of, dozen B. dozens of, dozens C. dozens of, dozen D. dozens of, dozen of此题最佳答案为C。
关于dozen的复数是否加词尾-s的问题比较复杂，大致原则是：1.当它与具体数字连用时，既不加复数词尾-s，也不后接介词of。
尽管有的词书也有two dozen of 这样的用例，但这已属过时用法，在考试中应避免：Shortly after the accident, _________ police were sent to the spot to keep order.A. dozens ofB. dozensC. dozen ofD. dozen [D]2. 当它不与具体数字连用，而是表示不确定的泛指数时，则不仅要加复数词尾-s，而且要后接介词of，此时可将dozens of(许多，几十)视为习语。
如：I’ve been there dozens of times.Dozen的用法: 请先看下面一道试题：We already have _________ pencils, but we need two _________ pens. A. dozen of, dozen B. dozens of, dozens C. dozens of, dozen D. dozens of, dozen of此题最佳答案为C。
关于dozen的复数是否加词尾-s的问题比较复杂，大致原则是：2.当它与具体数字连用时，既不加复数词尾-s，也不后接介词of。
尽管有的词书也有two dozen of 这样的用例，但这已属过时用法，在考试中应避免：Shortly after the accident, _________ police were sent to the spot to keep order.A. dozens ofB. dozensC. dozen ofD. dozen [D]2. 当它不与具体数字连用，而是表示不确定的泛指数时，则不仅要加复数词尾-s，而且要后接介词of，此时可将dozens of(许多，几十)视为习语。
【最新】dozen用法的方方面面-word范文模板 (2页)
【最新】dozen用法的方方面面-word范文模板本文部分内容来自网络整理，本司不为其真实性负责，如有异议或侵权请及时联系，本司将立即删除！== 本文为word格式，下载后可方便编辑和修改！ ==dozen用法的方方面面dozen用法的方方面面& nbsp ;有这样一道题，涉及 dozen 用法的多个方面，你做得对吗？We already have ______ pencils , but we need two ______ pens .http :// yingyu . chazidian . comA. dozen of, dozen & nbsp ;& nbsp ;& nbsp ;& nbsp ;& nbsp ; & nbsp ;& nbsp ;& nbsp ;& nbsp ;& nbsp ;& nbsp ;& nbsp ;& nbsp ;& nbsp ;  ;& nbsp ;& nbsp ;& nbsp ;& nbsp ;& nbsp ;& nbsp ;& nbsp ;  ;& nbsp ; B. dozen s of, dozen sC. dozen s of, dozen & nbsp ;& nbsp ;& nbsp ;& nbsp ;& nbsp ;  ;& nbsp ;& nbsp ;& nbsp ;& nbsp ;& nbsp ;& nbsp ;& nbsp ;  ;& nbsp ;& nbsp ;& nbsp ;& nbsp ;& nbsp ;& nbsp ;& nbsp ;  ;& nbsp ; D. dozen s of, dozen of【分析】此题最佳答案为C。
高二英语 单元单词短语句型知识梳理 Unit 第二册_4
得夺市安庆阳光实验学校Unit 20理解:要点诠释单词1.dozen讲：n. 十二；(一)打例:Give me a dozen,please.请给我来一打。
Only about half a dozen turned up.只有六七个人到了。
He bought three dozen red roses for her on Valentine’s Day.在情人节他给她买了三打红玫瑰。
链接·提示(1)dozen作“十二”讲，其前有数词或a,few,several,many等词修饰时，用单数形式；若后面接代词时，dozen后of不能省略。
a,few,several,many修饰dozen其后of可有可无。
类似单词还有score,handred,thousand,million。
(2)dozens of许多；scores of许多。
练:Apples are usually sold by _________ weight,and eggs are sometimes sold by____________ dozen.A.the;theB./;aC./;theD.the;a提示:本题看似考查冠词，实际上考查固定搭配:by weight意为“按(论)重量；by the dozen意为“论打”。
答案:C2.spare讲：v. 抽出；拔出；留出；匀出；省得；免得；饶恕；赦免；放过adj. 空闲的；多余的；备用的n.备用品例:I’d love to have a rest,but I can’t spare the time just now.我想休息一下，但眼下找不出时间。
We can only spare one room for you.我们只能给你腾出一个房间。
He wanted to spare his mother any anxiety.他不想让母亲有丝毫的担忧。
During the bombing only one house was spared.在轰炸中，只有一座房子幸免。
英语 a dime a dozen 的用法
当有人对你说a dime a dozen 时，可千万别只理解成“一毛钱一打”，这个短语的引申意思是“很普遍；不值钱”，怎么样，是不是很有意思呢？我们还是赶快来学习一下它的用法吧。
例句1：Digital note-taking apps are a dime a dozen, and I've tried a pretty good chunk of them.
数字笔记应用程序很普遍，我已经尝试了相当多。
例句2：But this sort of innovation is a dime a dozen nowadays.
但这种创新在今天已经不稀罕物了。
例句3：In Hollywood, pretty girls are a dime a dozen.
在好莱坞漂亮姑娘多的是。
例句4：I don't need friends like him; they are a dime a dozen.
我不需要他这样的朋友，他们太廉价了。
例句5：Tiny MP3 players are a dime a dozen nowadays — but how many have Bluetooth?
现在市场中，小巧的MP3播放器相当普遍，但当中又有多少具备蓝牙功能呢？
用法小结：
通过以上学习，大家可以体会到，a dime a dozen 是一个形容词短语，用于表达“很普遍；不稀奇；不值钱”等意思。
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【奇速英语】点拨英语词汇dozen的用法
dozen可用复数吗？dozen后要接of吗？你知道dozen的用法吗？请先看下面一道试题：
We already have _________ pencils, but we need two _________ pens. A. dozen of, dozen B. dozens of, dozens C. dozens of, dozen D. dozens of, dozen of
此题最佳答案为C。
关于dozen的复数是否加词尾-s的问题比较复杂，大致原则是：
1. 当它与具体数字连用时，既不加复数词尾-s，也不后接介词of。
尽管有的词书也有two dozen of 这样的用例，但这已属过时用法，在考试中应避免，如1992年全国高考有一道单项选择题就认为two dozen of为错误选项：
Shortly after the accident, _________ police were sent to the spot to keep order.
A. dozens of
B. dozens
C. dozen of
D. dozen [D]
2. 当它不与具体数字连用，而是表示不确定的泛指数时，则不仅要加复数词尾-s，而且要后接介词of，此时可将dozens of(许多，几十)视为习语。
如：
I’ve been there dozens of times. 我去过那儿几十次。
She’s got dozens of boy-friends. 她的男朋友很多。
下面一例中的dozens加了复数词尾-s也属为似情况：
Pack them in dozens. 按打装袋吧。
(from )
奇速英语官网供稿 1
3. 当与a few, several 等数目不很具体的词连用时，加不加复数词尾-s均可，但需注意：不加复数词尾-s时，其后的介词of可以省略；加词尾-s时，其后介词of不能省略。
如：
several dozen (of) pencils=several dozens of pencils几打铅笔
注：英语较少使用many dozen的说法，要表示类似意思可用dozens of。
4. 当它后面的名词受the, these, those 等特指限定词修饰时，或其后的接的是us, them这样的人称代词时，则此时必须用介词of。
如：two dozen of these eggs 两打这种鸡蛋
three dozen of them 它们中的3打
注：score, hundred, thousand, million等也具有以上类似用法。
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