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裕兴新概念英语第二册笔记-第79课(汇编)

裕兴新概念英语第二册笔记-第79课(汇编)
裕兴新概念英语第二册笔记-第79课(汇编)

Lesson 79 By air乘飞机

Why did the plane turn back?

I used to travel by air a great deal when I was a boy. My parents used to live in South America and I used to fly there from Europe in the holidays. A flight attendant would take charge of me and I never had an unpleasant experience. I am used to traveling by air and only on one occasion have I ever felt frightened. After taking off, we were flying low over the city and slowly gaining height, when the plane suddenly turned round and flew back to the airport. While we were waiting to land, a flight attendant told us to keep calm and to get off the plane quietly as soon as it had touched down. Everybody on board was worried and we were curious to find out what had happened. Later we learnt that there was a very important person on board. The police had been told that a bomb had been planted on the plane. After we had landed, the plane was searched thoroughly. Fortunately, nothing was found and five hours later we were able to take off again.

参考译文

我在幼年的时候,曾多次乘飞机旅行。我的父母曾经住在南美洲,所以假期里我常从欧洲乘飞机到他们那里。我总是由一位空中乘务员照管,从未遇到过不愉快的经历。我习惯了乘飞机旅行,只是有一次把我吓坏了。起飞之后,我们在城市上空低低地飞行,然后慢慢爬高。这时飞机突然调转头来,飞回了机场。在我们等待降落时,一位空中乘务员告诉我们要保持镇静,待飞机一着陆,就马上不声不响地离开飞机。飞机上的人都很着急,大家都急于想知道究竟出了什么事。后来我们才得知,飞机上坐了一位非常重要的人物。有人报告警察,说飞机上安放了一枚炸弹。我们降落之后,飞机被彻底搜查了一遍。幸运的是,什么也没有找到。5个小时后,我们又起飞了。【New words and expressions】(6)

1 parent ['pe?r?nt] n.父(母)亲

2 flight attendant['flait ??tend?nt] 空中乘务员

3 frightened['fraitnd] a.害怕,担惊

4 curious ['kju?ri?s] a.急于了解,好奇的

5 bomb [b?m] n.炸弹

6plant[plɑ:nt] v.安放

一、单词讲解

parent

1)n.父母(pl.)(通常以复数的形式出现)

eg. John and Mary have become parents.

约翰和玛莉已为人父母了。

relation 家人

to invite all your relations to dinner

(邀请全家人来吃饭)

relative (正式)家人,亲戚(更常用)

eg. My uncle is my nearest relative.

我的叔父是我最亲的亲人。

2) n.(定语)能繁殖的任何生物

the parent tree 母树

parent company 母公司

Parentage 出身,身世

a child of unknown parentage 身世不明的小孩

Parenthood 父母的身份或情况

flight attendant空中乘务员

air-hostess 空姐

flight n.

1)班机,航班

eg. Flight number 447 for Geneva is ready to leave.

飞往日内瓦的447次航班准备出发。

2)航程,飞行距离

a straight flight towards home直航回家

3)航空旅程

eg. Did you have a good flight? 你搭乘飞机一路愉快吗?

attendant n.(公共场所照顾游客的)服务员

a flight attendant 空中乘务员

a museum attendant 博物馆接待员

shop assistant (在店里工作的)店员

frightened adj.受惊的,吃惊的

eg. The frightened horse ran away from the fire.

受惊的马从大火中逃跑了。

He was frightened at the thought of his coming examination.

一想到即将到来的考试他就害怕。

She was frightened to look down from the top of the tall building. 她害怕从高楼顶上往下看。

The little girl was frightened that her mother wouldn't come back. 小女孩怕她妈妈不回来了。

afraid adj. 害怕的

be afraid of 害怕某物

be afraid of dogs 害怕狗

be afraid that 害怕某事物(后面加从句)

be afraid to do 害怕做某事

frightening adj.令人受惊的

a frightening dream 吓人的梦

frightful adj.可怕的,惊人的

a frightful scene 可怕的景象

frighten

1)V。使吃惊,惊吓

eg. The little girl was frightened by the big dog.

那个小女孩被大狗吓到了。

2)v.吓走

eg. He frightened off his attacker by calling for the police.

他叫警察吓走了袭击者。

fright n. 害怕

get a fright 吓了一跳

curious adj.

1)急于了解的,好奇的

eg. A good student should always be curious to learn.

好学生应有求知欲。

He was so curious to know what was in the letter that he opened it, even though it was addressed to his father.

他如此好奇想知道信的内容,于是他打开了信,尽管信是写给他父亲的。

2)好管闲事的

eg. My neighbors are very curious.我的邻居们非常好管闲事。

curiosity n.好奇,好奇心

out of curiosity 出于好奇心

eg. The boy burned with a curiosity to know what was in the letter addressed to his mother.

这个孩子极想知道写给妈妈的信里的内容。

bomb形近词:comb梳子

1)炸弹

plant a bomb in the post office(在邮局安放一枚炸弹)

2)原子弹

Has that country got the bomb? (那个国家有原子弹吗?)

习语:

go like a bomb (指交通工具)行进快速,疾驶

eg. My new car goes like a bomb.我的新车行驶的非常快。

spend/cost a bomb花了许多钱

bomber 轰炸机

fighter 战斗机

plant

V.安放

eg. He planted himself in a chair by the fire.

他稳坐住炉边的椅子上。

He planted a knife in her back. 他在她背上插了一刀。

2)v.种植

eg. April is the time to plant.

3)v.播种,培植

eg. The hillside was planted with trees.山坡上种满了树

4) n.植物

eg. All plants need water and light.

所有的植物需要水和阳光。

5)n.工厂

eg. They've just built a new chemical plant.

他们刚刚建立了一个新的化工厂。

二、关键句型Key Structures

过去时/过去进行时

used to do/was (were) +doing

used to do过去常常做某事(通常表示跟现在形成对比的,过去常常做而现在不做了)

was(were)doing过去某时正在做某事(过去进行式)

Exercise 1.用正确的时态填空:

2) After taking off, we ___(fly) low over the city and slowly___(gain) height.

分析:take off 起飞

起飞之后,我们在城市上空低低地飞行然后慢慢爬高。

After taking off我们叮以用这种进行时态表示当时我们正在做某事,描述故事背景。所以我们使用两个进行时态表示过去故事的背景,故应依次填入were flying;gaining

2)While we were waiting to land, a flight attendant____ (tell)us to keep calm.

分析:该语句的意思是当我们等待降落的时候,一位空中乘务员告诉我们要保持镇静。

故事的背景是我们等待着降落,那么过去的故事是一般过去式,故应填入told。

3)I ____ (used) to travel by air a great deal when I was a boy.

分析:该语句的意思是当我小的时候我总是乘飞机旅行。

时间状语是when I was a boy,当我还是幼年的时候(当我还小的时候)我总是乘飞机旅行,那么表示过去某时经常做某事应该用used to do sth,故应填入used。

Exercise 2.解释以下两个句子在词义上的不同点:

I)I used to fly there from Europe in the holidays. (过去常常)

在假期里,我常从欧洲乘坐飞机到那里去。

2)I am used to traveling by air.(习惯于,后面加名词、代词、动名词做介词to的宾语)

我习惯于坐飞机旅行了。

三、课文讲解Text

I used to travel by air a great deal when I was a boy. My parents used to live in South America and I used to fly there from Europe in the holidays. A flight attendant would take

charge of me and I never had an unpleasant experience.

take charge of 负责照料(某人谋物)

eg. Can you take charge of this class please, Miss Jones?

琼斯小姐能照料这个班吗?

in someone' s charge / under someone' s charge

受管理,由(某人)负责

eg. This hospital is in her charge until the director comes back.

在主管回来之前,这家医院由他负责。

in charge of负责

eg. I' II be in charge of the whole factory next week when he director is away.

下周厂长不在的时候,我负责整个工厂。

bring a charge against 控告(某人)

eg. The police brought a charge of murder against me.

警方控告我谋杀。

unpleasant adj.不愉快的,讨厌的

unpleasant smells 恶心的气味

unpleasant weather 讨厌的天气

a few unpleasant words 一些难听的话

an unpleasant experience 不愉快的经历

unpleasantness n.不愉快

eg. Don' t let the recent unpleasantness end our friendship.

不要让眼下这些不愉快终止我们的友谊。

un + adj.构成相反含义的adj.

unpracticed 笨手笨脚的

unprincipled 无原则的,无廉耻的

unprofessional 司E本行的

unmannerly 粗鲁的

unmarried 未婚的

unknown 不知道的;不知名的

unfortunate 不幸的

unforgettable难以忘怀的

I am used to traveling by air and only on one occasion have I ever felt frightened.

be used to习惯于(to为介词)

be used to doing/be used to sth

eg. I am used to traveling by air.(我习惯于乘飞机旅行了)

I am not used to drinking.(我不习惯于喝酒)

A man used to country life(习惯于乡村生活的男子)

only on one occasion仅仅有一次

only(seldom, hardly) +状语放在句首时,用倒装句。

eg. Only in this way can you hope to improve the situation there.

只有用这种方式你才有希望改善那的状况。

only in this way是方式状语,放于句首的时候后面应使用倒装语VU。我们把can提前you放后面称为是部分倒装。

Hardly had he finished when someone rose to refute his views.

他刚讲完就有人站起来驳斥他的观点。

Scarcely had she fallen asleep when a knock at the door awakened her.

她刚一睡着就被敲门声吵醒了。

Not until quite recently did I have any idea what a guided missile was like.

直到最近我才清楚导弹是什么样子的。

以never,little,often,等词引起的句子,也常用倒装语序。

Never before has our country been as united as it is today.

今天我们的国家空前团结。

Many a time has he given us good advice.

他有很多次给我们好的建议。

Little did we suspect that the district was so rich in mineral resources.

我们一点也没有想到这个地区的矿产资源如此丰富。

Often did we warn them not to do so.

我们经常警告他不要这么做。

After taking off, we were flying low over the city and slowly gaining height, when the plane suddenly turned round and flew back to the airport.

take off 起飞

fly low over 在…上方低低地飞行

fly back to 飞回

fly

1) v. 飞,飞行

eg. "How did you get here?" "I flew. "

‘‘你怎么来的?” “我飞回来的。”

这里“I flew”木目当于“I came by airport”

A bee flew in though the open window.

一只蜜蜂从开着的窗户飞了进来。

2)V.开飞机

eg. He was the first man ever to fly that type of aircraft.

他是第一个驾驶那种飞机的人。

3)V.搭乘飞机

eg. I always fly British Airways.我经常搭乘英航飞机。

fly习语:

eg. I must fly.(口)急忙离去

fly into a temper 勃然大怒

The bird has flown 犯人逃亡了

make the dust fly/make the fur fly/make the sparks fly

引起争吵

slowly/gradually 慢慢的;缓慢的;逐渐的:

gain height 爬高

gain speed 加速

gain experience 获得经验

when相当于at that time

turn around 调头(turn round)

turn back

1)往回走

2)把某页的角折起来

eg. Turn the page back and it will mark your place.

把某一页折个角,做个记号。

turn down

1)减弱,降低

eg. Turn that radio down at once!马上把收音机声音降低.

2)拒绝

eg. She turned him down.她拒绝了他。

turn in

1)归还

仔C: You must turn in your uniform when you leave the army.

当你离开部队的时候,你必须归还制服。

2)(美)交,缴

eg. This is a poor piece of work you've turned in.

你交的作品很糟糕。

While we were waiting to land, a flight attendant told us to keep calm and to get off the plane quietly as soon as it had touched down.

land v.着陆

eg. This plane can land anywhere.

这架飞机可以往任何地方着陆。

keep calm 保持镇定

keep +adj. 保持某一状态

keep warm 保暖keep silent保持沉默

tell sb to do sth 告诉某人去做某事

tell us to keep calm 告诉我们保持镇定

tell us to get off the plane quietly告诉我们安静地下飞机

touch down/land 飞机着陆

Everybody on board was worried and we were curious to find out what had happened.

on board 在…(如飞机、船上)上

go by the board (指计划,安排等)完全失败

sweep the board 在选举中获全胜

above board 完全公开而手段正当的

be curious to do 好奇做

Later we learnt that there was a very important person on board.

learn/know 得知

very important person 非常重要的人缩写为VIP

VIP card 贵宾卡

on board 在飞机上

The police had been told that a bomb had been planted on the plane. After we had landed, the plane was searched thoroughly.

thoroughly/completely 彻底地;完全地

Fortunately, nothing was found and five hours later we were able to take off again.

take off

1)起飞

2)脱下(反义词:put on)

eg. He took off his coat.他脱下他的外套。

3)模仿(以诙谐或嘲讽的方式模仿或假扮某人)

eg. He is always taking his teacher off.

他总是模仿他的老师。

take after(在长相或性格方面)像;长得像(父亲或母亲)

eg. Young Tom takes after his father.

小汤姆长得很像他的父亲。

(这里take after相当于resemble)

take

1)填满,占据(空间或时间)

eg. The wardrobe takes up a lot of space.

(相当于The wardrobe occupies a lot of space)

那个衣柜很占地方。

2)开始从事某事

eg. He has taken up French ./ He has begun to learn French.

他开始学法语了。

take to逐渐习惯于做某事(+n./doing)

eg. When his wife died, he took to drinking

take in欺骗,蒙骗或愚弄某人

eg. He was so persuasive that I was taken in.

/He was so persuasive that I was deceived.

他真能说,我被欺骗了。

take down(write down)写下,记下

eg. The reporter took down everything I said.

记者把我说的话都记了下来。

take over接收,接管(be in charge of)

eg. The business was doing very badly until Jones took over.

琼斯经营这个公司之前公司很差。

课文难点

有关take的短语Exercise

用正确的词填空

l) Who will take _____ , when the present director leaves?

现在的主管离开后谁会接管呢?故应填入over。

2) As soon as he got into the lift he took his hat ____.

他一进电梯就把帽子摘了下来。故应填入off。

3)You shouldn't be taken ____. by storied like that.

你不应该被那样的故事所欺骗。表示欺骗或蒙蔽的,故应填入in。

4)He takes people_ so well he ought to go on the stage.

他模仿人如此的像,他应该去表演。故应填入after。

5) Last year he took ____ Russian; now he is taking_ Chinese.

他去年学俄语,今年他改学汉语了。表示开始做某事,故应填入up。

6) None of my children takes me.

我的孩子没有一个长得像我。表示长得像的,故成填入after。

7) The new rocket will take _____ from Cape Canaveral.

火箭将从Cape Canaveral发射出去。表示起飞或发射,应填入off。

8)Please take ____ this letter for me. Pamela, the manager said. 经理说把信写下来。写下来、记下为take down,应填入down。

四、练习Exercises

l. She would take charge of me. She was __D__.

A. dutiful

B. commanding

C. charging

D. responsible

分析:A.尽职的,尽责任的;B.指挥的,有控制力的:

C.充填的,充电的:D.负责的,对…有责任的。

2. I am used to traveling by air, I am __A__ to it

A. accustomed

B. . habitual

C. customary

D. inhabited

分析:A.习惯性的,适应了的,通常作表语;

B。习惯性的,通常的,常做定语;

C.习惯-上的,合乎习俗的,惯例的;

D.有人居住的。

3. We were curious to find out .We _C_.

A. were strange

B. were odd C wanted to know D. were peculiar

分析:A.陌生的,不平常的,奇怪的,古怪的:

B.奇特的,古怪的:C.想要知道:

D.奇怪的,乖僻的,特别的。

4. On his trip __B__ he visited relatives in Japan

A. aboard

B. abroad

C. overseas

D. hoard

分析:A和D选项是词形相近的词,但词义不大一样;aboard是副词,表示“上船,上飞机或上火车”的意思:board是名词,基本含义上是“木板”在去国外的途中,他拜访了在日本的亲属。

六、补充内容

谚语

1) There are plenty of fish in the sea. 相当于

There are more good fish in the sea.

许多损失都可由其它同样好的东西来弥补;海里有的是鱼。

[用法]:常用于安慰失恋者等。

2) There is one born every minute.

随时有人上当;总会有人上当的。

真空泵的分类

真空泵是用各种方法在某一封闭空间中产生、改善和维持真空的装置。真空泵可以定义为:利用机械、物理、化学或物理化学的方法对被抽容器进行抽气而获得真空的器件或设备。随着真空应用的发展,真空泵的种类已发展了很多种,其抽速从每秒零点几升到每秒几十万、数百万升。极限压力(极限真空)从粗真空到10-12Pa以上的超高真空范围。 由于真空应用部门所涉及的工作压力的范围很宽,因此任何一种类型的真空泵都不可能完全适用于所有的工作压力范围,只能根据不同的工作压力范围和不同的工作要求,使用不同类型的真空泵。为了使用方便和各种真空工艺过程的需要,有时将各种真空泵按其性能要求组合起来,以机组型式应用。 凡是利用机械运动(转动或滑动)以获得真空的泵,称为机械真空泵。机械真空泵按其工作原理及结构特点分述如下: 1、变容真空泵 它是利用泵腔容积的周期变化来完成吸气和排气以达到抽气目的的真空泵。气体在排出泵腔前被压缩。这种泵分为往复式及旋转式两种。 (1)往复式真空泵 利用泵腔内活塞往复运动,将气体吸入、压缩并排出。又称为活塞式真空泵。 (2)旋转式真空泵 利用泵腔内转子部件的旋转运动将气体吸入、压缩并排出。它大致有如下几种分类: a、油封式真空泵 它是利用真空泵油密封泵内各运动部件之间的间隙,减少泵内有害空间的一种旋转变容真空泵。这种泵通常带有气镇装置。它主要包括旋片式真空泵、定片式真空泵、滑阀式真空泵、余摆线真空泵等。 b、液环真空泵 将带有多叶片的转子偏心装在泵壳内。当它旋转时,把工作液体抛向泵壳形成与泵壳同心的液环,液环同转子叶片形成了容积周期变化的几个小的旋转变容吸排气腔。工作液体通常为水或油,所以亦称为水环式真空泵或油环式真空泵。 c、干式真空泵 它是一种泵内不用油类(或液体)密封的变容真空泵。由于干式真空泵泵腔内不需要工作液体,因此,适用于半导体行业、化学工业、制药工业及食品行业等需要无油清洁真空环境的工艺场合。 d、罗茨真空泵 泵内装有两个相反方向同步旋转的双叶形或多叶形的转子。转子间、转子同泵壳内壁之间均保持一定的间隙。 2、动量传输泵 它依靠高速旋转的叶片或高速射流,把动量传输给气体或气体分子,使气体连续不断地从泵的入口传输到出口。这类泵可分为以下几种形式: (1)分子真空泵 它是利用高速旋转的转子把动量传输给气体分子,使之获得定向速度,从而被压缩、被驱向排气口后为前级抽走的一种真空泵。这种泵具体可分为: a、牵引分子泵

【第二次修订完全版】新概念英语第二册笔记pdf(96课全)

目录 Lesson 1 A private conversation 私人谈话 (4) Lesson 2 Breakfast or lunch? 早餐还是午餐 (11) Lesson 3 Please send me a card 请给我寄一张明信片 (16) Lesson 4 An exciting trip 激动人心的旅行 (21) Lesson 5 No wrong numbers 无错号之虞 (25) Lesson 6 Percy Buttons 珀西.巴顿斯 (31) Lesson 7 Too late 为时太晚 (38) Lesson 8 The best and the worst最好的和最差的 (44) Lesson 9 A cold welcome 冷遇 (49) Lesson 10 Not for jazz不适于演奏爵士乐 (55) Lesson 11 One good turn deserves another礼尚往来 (60) Lesson 12 Goodbye and good luck 再见,一路顺风 (64) Lesson 13 The Greenwood Boys 绿林少年 (68) Lesson 14 Do you speak English? 你会讲英语吗? (74) Lesson 15 Good news 佳音 (80) Lesson 16 A polite request 彬彬有礼的要求 (85) Lesson 17 Always young 青春常驻 (90) Lesson 18 He often does this! 他经常干这种事! (96) Lesson 19 Sold out 票已售完 (99) Lesson 20 One man in a boat 独坐孤舟 (104) Lesson 21 Mad or not? 是不是疯了? (110) Lesson 22 A glass envelope 玻璃信封 (115) Lesson 23 A new house 新居 (119) Lesson 24 It could be worse 不幸中之万幸 (122) Lesson 25 Do the English speak English? 英国人讲的是英语吗? (125) Lesson 26 The best art critics 最佳艺术评论家 (130) Lesson 27 A wet night 雨夜 (136) Lesson 28 No parking 禁止停车 (143) Lesson 29 Taxi! 出租汽车! (149) Lesson 30 Football or polo?足球还是水球? (154) Lesson 31 Success story 成功者的故事 (159) Lesson 32 Shopping made easy 购物变得很方便 (165) Lesson 33 Out of the darkness 冲出黑暗 (171) Lesson 34 Quick work 破案“神速” (177) Lesson 35 Stop thief! 捉贼 (180) Lesson 36 Across the Channel 横渡海峡 (186) Lesson 37 The Olympic Games 奥林匹克运动会 (193) Lesson 38 Everything except the weather 唯独没有考虑到天气 (198) Lesson 39 Am I all right? 我是否痊愈? (203) Lesson 40 Food and talk 进餐与交谈 (208) Lesson 41 Do you call that a hat? 你把那个叫帽子吗? (213)

裕兴新概念英语第一册笔记完整版[1]

裕兴新概念英语第一册笔记完整版 ?1)v. 原谅 ?eg. Excuse me. 请原谅,劳驾。 2)n. 借口 ?eg. It?s an excuse. ?me pron. 我(宾格:用来做宾语的。) ?eg. He loves me. 他爱我. ?eg. She cheats me. 他骗我. ?eg. Please tell me. 他告诉我. Excuse me 的用法 这个短语经常被译作“对不起”,但它并不表示你有什么过错,而是说你要打搅别人,所以常被译作“劳驾”。1)为了要引起别人的注意 ?eg. Excuse me. Is this you handbag? 2)要打扰某人或要打断别人话 ?eg. Excuse me . May I ask you a question? 3) 向陌生人问路 ?eg. Excuse me. Could you please tell me the way to the railway station? 4) 向某人借东西 ?eg. Excuse me. Can I bor row your pen? 5) 需要从别人身边挤过或让别人给自己让路 ?eg. Excuse me. Could you please make some room for me? 6) 要求在宴席或会议中途中离开一会儿 eg. Excuse me. May I lease for a little while? ?sorry 用于当你做错事而向别人道歉的时候,表示“对不起”。 1)请问几点了? ?eg. Excuse me. What time is it? 2) 不小心把水弄到了别人的身上。 ?eg. Sorry. 或者I?m sorry! 3) 对不起,我先失陪一下 ?eg. Excuse me. 4) 误解了别人的意思 ?eg. Sorry. ?yes 1)adv. 是的(对一般疑问句的肯定回答) ?eg. Are you mad? --Yes, I am. 2)经常用于应答,表示“什么事”。 ?eg. Excuse me? 请问/劳驾? ---Yes? 什么事? ?is v. be 动词现在时第三人称单数 ?be : is am are ?is 用于单数名词或单数第三人称代词。 ?eg. He is a student. 他是一个学生。 ?eg. That?s an egg. 那是一个鸡蛋。(That?s= That is)

真空泵的选型及常用计算公式

真空泵选型 真空泵的作用就是从真空室中抽除气体分子,降低真空室内的气体压力,使之达到要求的真空度。概括地讲从大气到极高真空有一个很大的范围,至今为止还没有一种真空系统能覆盖这个范围。因此,为达到不同产品的工艺指标、工作效率和设备工作寿命要求、不同的真空区段需要选择不同的真空系统配置。为达到最佳配置,选择真空系统时,应考虑下述各点: 确定工作真空范围: ----首先必须检查确定每一种工艺要求的真空度。因为每一种工艺都有其适应的真空度范围,必须认真研究确定之。 确定极限真空度 ----在确定了工艺要求的真空度的基础上检查真空泵系统的极限真空度,因为系统的极限真空度决定了系统的最佳工作真空度。一般来讲,系统的极限真空度比系统的工作真空度低20%,比前级泵的极限真空度低50%。 被抽气体种类与抽气量 检查确定工艺要求的抽气种类与抽气量。因为如果被抽气体种类与泵内液体发生反应,泵系统将被污染。同时必须考虑确定合适的排气时间与抽气过程中产生的气体量。 真空容积 检查确定达到要求的真空度所需要的时间、真空管道的流阻与泄漏。 考虑达到要求真空度后在一定工艺要求条件下维持真空需要的抽气速率。 主真空泵的选择计算 S=2.303V/tLog(P1/P2) 其中: S为真空泵抽气速率(L/s) V为真空室容积(L) t为达到要求真空度所需时间(s)

P1为初始真空度(Torr) P2为要求真空度(Torr) 例如: V=500L t=30s P1=760Torr P2=50Torr 则: S=2.303V/t Log(P1/P2) =2.303x500/30xLog(760/50) =35.4L/s 当然上式只是理论计算结果,还有若干变量因素未考虑进去,如管道流阻、泄漏、过滤器的流阻、被抽气体温度等。实际上还应当将安全系数考虑在内。目前工业中应用最多的是水环式真空泵和旋片式真空泵等 一般的要求是: 1、真空度、真空容积、主要介质、温度、主要容积类设备。 2、真空流入介质及流量、压力、温度、规律。 3、抽气量、抽出气体介质、温度。 4、真空设备的占地面积、自动化程度、真空管道规格 选用真空泵时需要注意事项: 1、真空泵的工作压强应该满足真空设备的极限真空及工作压强要求。如:真空镀膜要求1×10-5mmHg的真空度,选用的真空泵的真空度至少要5×10-6mmHg。通常选择泵的真空度要高于真空设备真空度半个到一个数量级。 2、正确地选择真空泵的工作点。每种泵都有一定的工作压强范围,如:扩散泵为10-3~10-7mmHg,在这样宽压强范围内,泵的抽速随压强而变化,其稳定的工作压强范围为5×10-4~5×10-6mmHg。因而,泵的工作点应该选在这个范围之内,而不能让它在10-8mmHg下长期工作。又如钛升华泵可以在10-2mmHg下工作,但其工作压强应小于1×10-5mmHg为好。

新概念英语第二册79课课后习题详细答案

新概念英语第二册课后习题答案详解Lesson 79 练习答案Key to written exercises 1.关键句型练习答案 A What happened: never had(1.4); turned round(1.7); flew back(1.7); told(1.8); learnt(1.10); was searched(1.11); was found(1.12); were able to take off(1.12) What was happening: were flying (1.6); and slowly gaining (1.6); were waiting(1.8) What used to/would happen: used to travel(1.1); used to live(1.2);used to fly(1.2);would take charge (1.3) C (sample answers) 1 In the past(but not now),I habitually flew there from Europe in the holidays. 2 I am accustomed to travelling by air now (because I have done it many times). 2.难点练习答案 1 over 2 off 3 in 4 up…up 5 after 6 off 7down 8 off 3.多项选择题答案 1. b 根据课文第6-7行,只有b. 与课文情形相符合,而其他3个选择都与课文内容不符,所以只能选b. 2. d 根据课文第11行,只有d. there was fear of an explosion (爆炸)是课文所暗示的情况,并能说明飞机返回的原因,而其他3个选择虽然都是课文所提及的内容,但不是飞机返

新概念英语第一册笔记(完整版)

新概念英语第一册 笔记完整版 ?1)v. 原谅 ?eg. Excuse me. 请原谅,劳驾。 2)n. 借口 ?eg. It?s an excuse. ?me pron. 我(宾格:用来做宾语的。)?eg. He loves me. 他爱我. ?eg. She cheats me. 他骗我. ?eg. Please tell me. 他告诉我. Excuse me 的用法 这个短语经常被译作“对不起”,但它并不表示你有什么过错,而是说你要打搅别人,所以常被译作“劳驾”。 1)为了要引起别人的注意 ?eg. Excuse me. Is this you handbag? 2)要打扰某人或要打断别人话 ?eg. Excuse me . May I ask you a question? 3) 向陌生人问路 ?eg. Excuse me. Could you please tell me the way to the railway station? 4) 向某人借东西 ?eg. Excuse me. Can I borrow your pen? 5) 需要从别人身边挤过或让别人给自己让路 ?eg. Excuse me. Could you please make some room for me? 6) 要求在宴席或会议中途中离开一会儿eg. Excuse me. May I lease for a little while? ?sorry 用于当你做错事而向别人道歉的时候,表示“对不起”。 1)请问几点了? ?eg. Excuse me. What time is it? 2) 不小心把水弄到了别人的身上。 ?eg. Sorry. 或者 I?m sorry! 3) 对不起,我先失陪一下 ?eg. Excuse me. 4) 误解了别人的意思 ?eg. Sorry. ?yes 1)adv. 是的(对一般疑问句的肯定回答)?eg. Are you mad? --Yes, I am. 2)经常用于应答,表示“什么事”。 ?eg. Excuse me? 请问/劳驾? ---Yes? 什么事? ?is v. be 动词现在时第三人称单数 ?be : is am are ?is 用于单数名词或单数第三人称代词。 ?eg. He is a student. 他是一个学生。 ?eg. That?s an egg. 那是一个鸡蛋。(That?s= That is) ?eg. This is a pen. 这是一支钢笔。 ?your 你的,你们的(物主代词后面加名词)?your key 你的钥匙 ?eg. This is your key. 这是你的钥匙。 ?eg. That is your book. 那是你的书。 ?your room 你们的房间 ?eg. That is your room. 那是你们的房间。 ?pardon 原谅,请再说一遍 ?pardon=pardon me=I beg your pardon? 能再说一遍吗? ?eg. Is this your pencil? 这是你的铅笔吗? --Yes, it is. 是的,它是。(it 指代 pencil) ?thank you 感谢你(们) 2)you 代词(你,你们) 主格-----作主语 ?eg. You are a good student. 你是一个好学生。 宾格------作宾语

新概念英语第二册笔记-第79课

-- Lesson 79By Air? 【Text】 Iused to travel by air agreat deal when I wasaboy. Myparents used tolive in SouthAmericaand I used tofly therefromEurope inthe holidays. A flight attendantwould takecharge of me and Inever hadan unpleasant experience. I amused to traveling by air andonly on one occasion haveI everfeltfrightened. Aft ertakingoff,we wereflying low over thecityandslowlygainingheight,whenthe plane suddenly turnedroundand flewback totheairport. Whilewewere waitingto land, a flight attendant told us to keepcalmand to get off theplanequietly as soon as it hadtoucheddown.Everybodyon board was worried and we were curious to find out whathadhappehttps://www.doczj.com/doc/cd15550410.html,ter welearnt thatthere was a veryimportant personon board. Thepolice hadbeento ld thatabomb had been planted on the plane. After we hadlanded,the plane was searched thoroughly. Fortunately,nothing wasfound and fivehours laterwe wer eable totake off again. 【课文翻译】 我在幼年的时候,曾多次乘飞机旅行。我的父母曾经住在南美洲, 所以假期里我常从欧洲乘飞机到他们那里。我总是由一位空中乘务员照管,从未遇到过不愉快的经历。我习惯了乘飞机旅行,只是有一次把我吓坏了。起飞之后,我们在城市上空低低地飞行,然后慢慢爬高。这时飞机突然调转头来,飞回了机场。在我们等待降落时,一位空中乘务员告诉我们要保持镇静,待飞机一着陆,就马上不声不响地离开飞机。飞机上的人都很着急,大家都急于想知道究竟出了什么事。后来我们才得知,飞机上坐了一位非常重要的人物。有人报告警察,说飞机上安放了一枚炸弹。我们降落之后,飞机被彻底搜查了一遍。幸运的是,什么也没有找到。5个小时后,我们又起飞了。 Newwordsand expressions生词和短语 【生词讲解】 1.parent 1)n父母(pl.) eg: Johnand Maryhave bec ome parents.

裕兴新概念英语第二册笔记 第82课

Lesson 82 Monster or fish? 是妖还是鱼? 【New words and expressions】(7) monster n. 怪物sailor n. 海员 sight v. 见到creature n. 动物,生物peculiar adj. 奇怪的,不寻常的 shining adj. 闪闪发光的oarfish n. 桨鱼 ★ monster (1)n. 怪物 a one-eyed monster獨眼怪物 eg:A dragon is a fabulous monster . 龍是一個傳說中的怪物 (2)巨大物、(做形容詞)巨大 eg:The spaceship was a real monster . 巨大的宇宙飛船 a monster pumpkin 南瓜 monstrous adj. 畸形的, 怪異的, 巨大的 a monstrous iceberg 巨大的冰山 monstrously adv. ひどく、非常に ★ sailor (1)n. 海员、水手 eg:His father is a sailor . (2)乘船的人(與adj. 連用) a good sailor 不暈船的人←→ a bad sailor 暈船的人 sail(同音詞sale)(1)n. 帆put up a sail 揚帆 (2)n.航行、航程go for a sail 乘船去航行 eg:It’s a forty-minute sail from Dove to Calais . 從多佛到加來需45分鐘的航行 in full sail 以全速;set sail 啟航 (3)v. 揚帆、航行,(使)行使 eg:The yacht sailed around the cape . 那艘遊艇繞岬航行。 eg:He sailed his boat into the harbor . 他將船直接駛向港口。 eg:Can you sail a yacht ?你會駕駛遊艇? sail close to the wind 幾乎犯法;冒風險 sailing n. 航海;sailing boat (英)帆船(美:sail boat)★ sight (1) v. 见到 eg:They sighted land at last . 他們終於看見陸地了 (2)n. 視力、視覺 near sighted =short sighted 近視 far sighted =long sighted 遠視 lose one’s sight 失明 (3)n. 視野 go out of sight 從視線消失、看不見了;come in sight 映入眼簾in sight 看得見,被見到;在望,在即 eg;I caught sight of his tall figure in the crowd . 在人群中我看見他高大的身影。

真空泵基础知识及选型指导

真空泵基础知识及选型指导 一、基础知识 1、真空的概念 “真空”一词来自拉丁语“vacuum”,原意为“虚无”、“空的”。真空是指在给定空间内低于环境大气压力的气体状态,即该空间内的气体分子密度低于该地区大气压力的气体分子密度,并不是没有物质的空间。水环真空泵应用于低真空(105—103 Pa)领域 2、真空的测量单位 在真空技术中,表示处于真空状态下气体稀薄程度的量称为真空度,可用压力、分子数密度、平均自由程和形成一个单分子层的时间常数等来表征,但通常用气体的压力(剩余压力)值来表示。气体压力越低,表示真空度越高;反之,压力越高,真空度越低。 法定的压力计量单位为帕[帕斯卡],符号为Pa 1Pa=1N.m-2 此外,还可用真空度的百分数作测量单位。 δ——真空度百分数(%)P——绝对压力(Pa)Pb-P 表示真空压力表读数,表压力(用Pe表示)真空度百分数δ(%)与压力P对照表 3、单位换算 1atm(标准大气压)=1013.25hPa(百帕) 1mmHg(毫米汞柱)=1Torr(托)=1.333 hPa(百帕) 1bar(巴)=1000 hPa(百帕) 1mbar(毫巴)=1 hPa(百帕)

1inHg(英寸汞柱)=25.4mmHg(毫米汞柱)=33.8 hPa(百帕) 4、相关术语 ◇气量——水环真空泵的气量是指入口在给定真空度下,出口为大气压1013.25hPa时,单位时间通过泵人口的吸入状态下的气体容积,m3/min 或m3/h 。 ◇最大气量——水环真空泵的最大气量是指气量曲线上的气量最大值,m3/min或m3/h。 ◇真空度(或称作压力)——水环真空泵的真空泵是指入口处在真空状态下气体的稀薄程度,以绝对压力表示,Pa、hPa、kPa。 ◇极限真空度(或称作极限压力)——水环真空泵的极限真空度是指入口处气量为零时的真空度,Pa、hPa、kPa。 ◇压缩比——吸入压力下气体容积与压缩后气体容积之比 ◇饱和蒸汽压——在给定温度下,某种物质的蒸汽与其凝聚相处于相平衡状态下的该种物质的蒸汽压力。 二、选型指导 真空泵的工作压力应该满足真空设备的极限真空及工作压力要求。通常选择泵的真空度要高于真空设备真空度半个到一个数量级。2BVX、2BEX 系列真空泵吸气压力范围在33hPa——1013.25 hPa之间,在此范围内,气量随吸气压力的不同而变化。根据气量和真空度选择合适的泵。保证工艺要求的真空度或抽走需要排走的气体。泵的工作点尽可能要求在高效区

新概念英语第二册第79课-By air

新概念英语第二册第79课:By air Lesson 79 By air乘飞机First listen and then answer the question. 听录音,然后回答以下问题。 Why did the plane turn back? I used to travel by air a great deal when I was a boy. My parents used to live in South America and I used to fly there from Europe in the holidays. A flight attendant would take charge of me and I never had an unpleasant experience. I am used to travelling by air and only on one occasion have I ever felt frightened. After taking off, we were flying low over the city and slowly gaining height, when the plane suddenly turned round and flew back to the airport. While we were waiting to land, a flight attendant told us to keep calm and to get off the plane quietly as soon as it had touched down. Everybody on board was worried and we were curious to find out what had happened. Later we learnt that there was a very important person on board. The police had been told that a bomb had been planted on the plane. After we had landed, the plane was searched thoroughly. Fortunately, nothing was found and five hours later we were able to take off again. 参考译文 我在幼年的时候,曾多次乘飞机旅行。我的父母曾经住在南美洲,所以假期里我常从欧洲乘飞机到他们那里。我总是由一位空中乘务员照管,从未遇到过不愉快的经历。我习惯了乘飞机旅行,只是有一次把我吓坏了。起飞之后,我们在城市上空低低地飞行,然后慢慢爬高。这时飞机突然调转头来,飞回了机场。在我们等待降落时,一位空中乘务员告诉我们要保持镇静,待飞机一着陆,就马上不声不响地离开飞机。飞机上的人都很着急,大家都急于想知道究竟出了什么事。后来我们才得知,飞机上坐了一位非常重要的人物。有人报告警察,说飞机上安放了一枚炸弹。我们降落之后,飞机被彻底搜查了一遍。幸运的是,什

新概念英语第二册笔记_第67课

Lesson 67 Volcanoes 火山 【Text 】 Haroun T azieff, the Polish scientist, has spent his lifetime studying active volcanoes and deep caves in all parts of the world. In 1948, he went to Lake Kivu in the Congo to observe a new volcano which he later named Kituro. Tazieff was able to set up his camp very close to the volcano while it was erupting violently. Though he managed to take a number of brilliant photographs, he could not stay near the volcano for very long. He noticed that a river of liquid rock was coming towards him. It threatened to surround him completely, but T azieff managed to escape just in time. He waited until the volcano became quiet and be was able to return two days later . This time, he managed to climb into the mouth of Kituro so that he could take photographs and measure temperatures. Tazieff has often risked his life in this way. He has been able to tell us more about active volcanoes than any man alive. 【课文翻译】 波兰科学家哈罗恩·塔捷耶夫花了毕生的精力来研究世界各地的活火山和深洞。1948年他去了刚果的基伍湖,对一座后来被他命名为基图罗的新火山进行观察。当火山正在猛烈地喷发时,塔捷耶夫有办法把帐篷搭在离它非常近的地方。尽管他设法拍了一些十分精彩的照片,但他却不能在火山附近停留太长的时间。他发现有一股岩浆正向他流过来,眼看就要将他团团围住,但塔捷耶夫还是设法及时逃离了。他等到火山平静下来,两天以后又返回去。这次他设法爬进了基图罗火山口,以便能拍摄照片和测试温度。塔捷耶夫经常冒这样的生命危险。他能告诉我们的有关活火山的情况比任何在世的人都要多。 New words and expressions 生词和短语 【生词讲解】 1. volcano n. 火山 (volcanoes) an active volcano 活火山 a dormant volcano 休眠火山 violently adv. 猛烈地,剧烈地 manage v. 设法 brilliant adj. 精彩的 liquid [5likwid] adj. 液态的;n. 液体 escape v. 逃脱 alive adj. 活着的

(完整版)新概念英语第一册笔记完整版

新概念英语第一册笔记完整版 ?1)v. 原谅 ?eg. Excuse me. 请原谅,劳驾。 2)n. 借口 ?eg.It?s an excuse. ?me pron. 我(宾格:用来做宾语的。) ?eg. He loves me. 他爱我. ?eg. She cheats me. 他骗我. ?eg. Please tell me. 他告诉我. Excuse me 的用法 这个短语经常被译作―对不起‖,但它并不表示你有什么过错,而是说你要打搅别人,所以常被译作―劳驾‖。 1)为了要引起别人的注意 ?eg. Excuse me. Is this you handbag? 2)要打扰某人或要打断别人话 ?eg. Excuse me . May I ask you a question? 3) 向陌生人问路 ?eg. Excuse me. Could you please tell me the way to the railway station? 4) 向某人借东西 ?eg. Excuse me. Can I borrow your pen? 5) 需要从别人身边挤过或让别人给自己让路 ?eg. Excuse me. Could you please make some room for me? 6) 要求在宴席或会议中途中离开一会儿 eg. Excuse me. May I lease for a little while? ?sorry 用于当你做错事而向别人道歉的时候,表示―对不起‖。 1)请问几点了? ?eg. Excuse me. What time is it? 2) 不小心把水弄到了别人的身上。 ?eg. Sorry. 或者I?m sorry! 3) 对不起,我先失陪一下 ?eg. Excuse me. 4) 误解了别人的意思?eg. Sorry. ?yes 1) adv. 是的(对一般疑问句的肯定回答) ?eg. Are you mad? --Yes, I am. 2)经常用于应答,表示―什么事‖。? eg. Excuse me? 请问/劳驾? ---Yes? 什么事? --我准备把它带给我的姐姐。 I‘m going to take it to my sister.

真空泵选型

产品名称:2BE 水环式真空泵

一、2BE水环式真空泵特点及用途: 2BE水环式真空泵及压缩机,是我厂在多年科研成果和生产经验的基础上,结合进口产品先进技术,研制开发的高效节能产品。通常用于抽吸不含固体颗粒,不溶于水,无腐蚀性的气体,以便在密闭容器中形成真空和压力。通过改变结构材料,亦可用于抽吸腐蚀气体或以腐蚀性液体做工作液。广泛用于造纸、化工、石化、轻工、制药、食品、冶金、建材、石器、洗煤、选矿、化肥等行业。 由于在工作过程中,该泵对气体的压缩是等温状态下进行,因此可抽吸易燃.易爆气体,通过改变结构材料,亦可抽吸腐蚀性气体货以腐蚀性液体作工作液。 2BE水环式真空泵采用单级单作用的结构形式,具有结构简单,维修方便,运行可靠,高效节能的优点。相对于目前国内广泛使用的SK、2SK、SZ系列水环式真空泵具有真空度高、功耗低等显著优点,是SK、2SK、SZ系列水环式真空泵理想替代产品 我公司生产的2BE型水环式真空泵及压缩机结构主要特点如下: 2BE型水环式真空泵的轴承全部采用NSK或NTN原装进口轴承,保证了2BE1真空泵的叶轮精确定位及运转过程中的高稳定性。 2BE型水环式真空泵的叶轮材质全部采用球墨铸铁铸造或钢板、不锈钢板焊接,充分保证了2BE1真空泵叶轮在各种恶劣工况下的稳定性,且大大 提高了2BE1真空泵的使用寿命。 泵体全部采用钢板或不锈钢板制作,提高了2BE1真空泵的使用寿命。 2BE1真空泵的轴套作为最易损坏的零件,本公司全部采用不锈钢制作,比普通材质寿命提高了5倍。 皮带轮(皮带传动)采用标准高精度锥套皮带轮,运行可靠,皮带寿命长,拆卸方便。 联轴器(直联传动)采用标准高强度弹性联轴器,弹性元件采用聚氨酯材质,运行稳定可靠,使用寿命长。 独特的上置式气水分离器节约空间,并有效降低了噪声。 铸件全部采用树脂砂铸造,表面质量好。铸件表面无需打腻,使2BE1真空泵散热效果最佳。 机械密封(选配件)全部采用进口件,充分保证2BE1系列真空泵在长时间运行过程中无泄漏。 二.2BE水环式真空泵特点: 1.高可靠性 由于该系列泵采用叶轮与轴热装过盈配合,轴与轴承安全系数大,因而具有相当搞的可靠性,叶轮采用焊接,轮及叶片全部加工,从根本解决了动平衡问题,运转平稳底噪音。 2.维护方便 由于在泵的端盖上没有设置检查孔,因而可以方便地查看内部结构,并无需拆泵便可更换排气阀板,此外填料的更换也可在不拆泵的情况下进行,释放方便。 3.高效节能 该系列泵采用系统优化设计,采用了柔性排气阀设计,避免了气体压缩中的过压缩,通过调节排气面积降低能量消耗,最终达到最佳运行效率。 4.适应冲击载荷 叶片采用钢板一次山冲压成型,型线得以保证,焊接叶轮整体进行热处理,叶片具有良好韧性,其抗冲击.

裕兴新概念英语第二册笔记打印版本

Lesson 1 A private conversation 【New words and expressions】 ★private ① adj. 私人的 private life 私生活private school 私立学校 ② adj. 普通的private citizen 普通公民 I‘m a private citizen. (citizen n. 公民) private soldier 大兵《Private Ryan》《拯救大兵瑞恩》) public adj. 公众的,公开的(private的反义词) public school 公立学校public letter 公开信 public place 公共场所privacy n.隐私 It‘s privacy. 这是我的隐私!(不愿让别人知道的) ★conversation n.谈话 have a + talk/chat/dialogue/conversation/gossip 名词变动词conversation 一般用于正式文体中, 内容上往往不正式subject of conversation 话题 They are having a conversation. talk 内容可正式可不正式, 也可以私人 Let‘s have a talk. dialogue 对话, 可以指正式国家与国家会谈 China and Korea are having a dialogue. chat 闲聊,就是北京人说的―侃‖,无关紧要的事。 gossip 嚼舌头, 说长道短 ★theatre n.剧场, 戏剧cinema n.电影院 ★seat n.座位 have a good seat/place,这里的seat指place(指地点),而不是chair. take a seat/take your seat 坐下来, 就坐 Is the seat taken? 这个位置有人吗? 请坐的3种说法: Sit down, please. (命令性) Take your seat, please. Be seated, please. (更礼貌) 作为动词的seat与sit的区别 sit(sat,)vi. 就座He is sitting there.他坐在那儿。 seat vt.让某人就座Seat yourself. seat sb. 让某人就坐,后面会加人 You seat him.你给他找个位置. When all those present(到场者)_D_ he began his lecture.A. sit B. set C. seated D. were seated sit down 坐下;be seated=take a seat 就坐 ★angry adj. 生气的 ★angrily adv. 生气的angry =cross I was angry. /He was cross. annoyed: 恼火的; be blue in the face 脸上突然变色 程I was annoyed. 度I was angry/cross. 加I was very angry. 深I am blue in the face. (脸色都青了,相当生气) ★attention n. 注意 Attention ,please. 请注意(口语) pay attention 注意pay attentio n to … 对……注意 You must pay attention to that girl. pay a little attention 稍加注意pay much attention 多加注意pay more attention 更多注意pay no attention 不用注意pay close attention 特别注意 ★bear(bore, born) v. 容忍 ① vt. 承受,支撑,承担,负担 Can the ice bear my weight? Who will bear the cost? 谁来承担这笔费用? ② vt. 忍受(与can/could连用于疑问及否定句中) She eats too fast. I can‘t bear to watch/watching her. How can you bear living in this place?

裕兴新概念英语第二册笔记 第79课

Why did the plane turn back I used to travel by air a great deal when I was a boy. My parents used to live in South America and I used to fly there from Europe in the holidays. A flight attendant would take charge of me and I never had an unpleasant experience. I am used to traveling by air and only on one occasion have I ever felt frightened. After taking off, we were flying low over the city and slowly gaining height, when the plane suddenly turned round and flew back to the airport. While we were waiting to land, a flight attendant told us to keep calm and to get off the plane quietly as soon as it had touched down. Everybody on board was worried and we were curious to find out what had happened. Later we learnt that there was a very important person on board. The police had been told that a bomb had been planted on the plane. After we had landed, the plane was searched thoroughly. Fortunately, nothing was found and five hours later we were able to take off again. 参考译文 我在幼年的时候,曾多次乘飞机旅行。我的父母曾经住在南美洲,所以假期里我常从欧洲乘飞机到他们那里。我总是由一位空中乘务员照管,从未遇到过不愉快的经历。我习惯了乘飞机旅行,只是有一次把我吓坏了。起飞之后,我们在城市上空低低地飞行,然后慢慢爬高。这时飞机突然调转头来,飞回了机场。在我们等待降落时,一位空中乘务员告诉我们要保持镇静,待飞机一着陆,就马上不声不响地离开飞机。飞机上的人都很着急,大家都急于想知道究竟出了什么事。后来我们才得知,飞机上坐了一位非常重要的人物。有人报告警察,说飞机上安放了一枚炸弹。我们降落之后,飞机被彻底搜查了一遍。幸运的是,什么也没有找到。5个小时后,我们又起飞了。 【New words and expressions】(6) parent 1)n.父母(pl.)(通常以复数的形式出现) eg. John and Mary have become parents. 约翰和玛莉已为人父母了。 relation 家人 to invite all your relations to dinner (邀请全家人来吃饭) relative (正式)家人,亲戚(更常用) eg. My uncle is my nearest relative. 我的叔父是我最亲的亲人。 2) n.(定语)能繁殖的任何生物 the parent tree 母树

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