if用法归纳
◇特别提醒
1. if作为“是否”的用法初二课本暂时没有涉及，只作拓展之用。
2. 以下内容只作了解，现行牛津初中教材内容已经删除。
在表示某一情形总会出现相同的结果时，if从句和主句都用一般现在时。
If the engine gets too hot, it starts to smoke. 发动机过热就会开始冒烟。
3. if在虚拟语气中的用法为高中内容，比较复杂，在此不作涉及。
◇课本例句
1. If you eat my food, I won’t talk to you. (P58)
2. If I don’t have food, I will die. (P58)
3. I f I don’t have food, I will die too. If I die, no one will look after you. (P58)
4. If hunters catch a giant panda, they will kill it for its fur. (P60)
5. If farmers cut down trees and forests, giant pandas will have nowhere to live. (P60)
6. If people find baby pandas alone, they will often take them away. (P60)
7. If we do nothing, soon there will be no giant pandas in the world! (P60)
◇词典例句
1. If we miss the last bus, we’ll have to walk home.
2. If it rains, we’ll have to go indoors.
3. If I have enough money next year, I will go to England.
4. What shall we do if it rains tomorrow?
5. She asked me if I was fond of music. 她问我是否喜欢音乐。
6. Can you tell me if they’re planning to come? 你能告诉我他们是否打算过来吗？
7. I don’t know if she’s coming. 我不知道她是否会来。
8. She asked me if I could go to the party. 她问我能不能去参加聚会。
◇相关词组
☆if you want/like 如果你愿意的话
You can come and stay with us if you want.
☆if so如果是的话
Are you planning to return to work, and if so, who is going to look after the baby? ☆if not如果不是的话
Has anyone dealt with the technical problems? And if not, why not?
☆if necessary/if possible 如果必要/可能的话
We are ready to fight for our rights if necessary.
I should like to be back here by 10:30 if possible.
☆even if即使
I’d rather never sell this painting, even if they offered me a million dollars.
☆what if 要是……，那怎么办？如果……那会怎样？
What if the boss walked in here now and saw us?
☆as if好像是……
She always talks to me as if she was my sister.
◇相关练习
动词填空：
1. If it ______ (be) sunny tomorrow, I ______( walk) to school .
2. We ________ (not have ) our sports meeting if the weather ____ (not be ) fine.
3. If it _______ (rain ), my father _____ (take ) me to school in his car .
4. Tigers _______ (hunt ) for their own food if they _____ (live) in the wild.
5. If wolves ________ (be) in the wild, they ______(live) as family groups.
6. If we don’t help the wild animals in danger, they ______ (die) soon.
单项选择：
( )1.I don’t know if he ______ tomorrow . If he _______, I will tell him about it .
A. will come; will come
B. comes ; comes
C. comes; will come
D. will come ; comes
( ) 2. If Simon ______ hard, he ______ good at English.
A. work; is
B. works; is
C. works; will be
D. will work; will be
( ) 3. He will come ________ you ask him.
A. whether
B. unless
C. if
D. while
( ) 4. If the phone _______, can you answer it ?
A. rings
B. is ringing
C. will ring
D. rang
( ) 5. Please give me a ring if you _______next Sunday.
A. won’t go
B. don’t go
C. not go
D. not to go
( ) 6.Do you know if his school _____a sports meeting next month.
A. hold
B. holds
C. to hold
D. will hold
( ) 7.We are not sure if it ______tomorrow. If it ______, we won’t climb the South Hill.
A. will now, snows
B. will snow, will snow
C. snows, snows
D. snows, will snow
( ) 8. If we do nothing, there_________ no more giant pandas.
A. will have
B. will has
C. will be
D. will be going to have ( ) 9. There_________ elephants if we don’t protect them.
A. won’t be any
B. will have no
C. won’t be some
D. will be some
( ) 10. ---- Do you want to go swimming this afternoon?
----Yes, if the weather_________ warm.
A. will be
B. would be
C. was
D. is
翻译句子：
1．If ___________________(如果明天不下雨的话), we will go to the zoo. 2．__________________(如果你生病了), you must see the doctor.
3．You’ll have to have a rest _______________（如果你感到累）
4．___________________(如果我们训练海豚), they perform tricks. 5．Parrots repeat words _______________________ (如果你教他们)
6．_____________(如果老虎住在野外), they will hunt for their own food .
7．If you do not hurry up, ________________________________.(你会上学迟到).
◇江苏13城市中考试题汇编
1. If those wild animals can’t find enough food, they ________ (die) or have to leave their habitat soon. (2010无锡)
( ) 2. A tourist will easily lose his way in Beijing ______ he has a map or guide. (2010镇江)
A. if
B. because
C. unless
D. when
( ) 3. ----Excuse me, could you take care of my little dog for me?
----________. I ________it if it doesn’t rain after supper. (09镇江)
A. Sorry; will walk
B. My pleasure; will walk
C. I’m sure; walk
D. I’m afraid not; walk
( ) 4. I have the key to the front door. My parents won’t wait for me if I ___________ back late. (09徐州)
A. come
B. will come
C. am coming D have come
5. 如果明天下雨，我们就在家做作业。(2010扬州)
_______________________________________________
Keys:
◇相关练习
动词填空：
1. is, will walk
2. won't have, isn't
3. rains, will take
4. will hunt, live
5. are, will live
6. will die
单项选择：
1~5 D C C A B 6~10 D A C A D
翻译句子：
1. it doesn't rain tomorrow
2. If you are ill
3. if you feel tired
4. If we train dolphins
5. if you teach them
6. If tigers live in the wild
7. you will be late for school
◇江苏13城市中考试题汇编
1. will die
2. C
3. B
4. A
5. If it rains tomorrow, we will do our homework at home.
as-if-用法归纳
as if 用法归纳 1． as if 从句的作用as if一般可由as though来代替。 引导表语从句，可在look, seem等系动词后。如： He looked as if / though he was ill. 他看起来好像生病了。It seems as if it is going to rain.看来好像要下雨了。 引导方式状语从句。如： I remember the whole thing as if / though it happened yesterday. The child talked to us as if he were a grown-up. 那个小孩跟我们讲话就像个大人一样。 2． as if 从句的语气及时态 ①as if从句用述语气。当说话者认为句子所述的是真实的或极有可能发生或存在的事实时， It sounds as if it is raining. 听起来像在下雨。 He talks as if he is drunk. 从他说话的样子来看他是醉了。 ②as if从句用虚拟语气。当说话人认为句子所述的是不真实的或极少有可能发生或存在的情况时， 表示与现在事实相反，谓语动词用一般过去式。如： You look as if you didn’t care. 你看上去好像并不在乎。When a pencil is partly in a glass of water, it looks as if it were broken． 表示与过去或与谈话时间为止发生的事实相反，谓语动词用
“had +过去分词”。如： He talked about the Great Wall as if he had been there before.说起长城来好像他以前去过那里。 The girl listened as if she had been turned to stone.女孩听着，一动也不动，像已经变成了石头。 表示与将来事实相反，谓语动词用“would / could / might + 动词原形”。如： He opened his mouth as if he would say something. 他开嘴好像要说什么。 It looks as if it might snow. 看来好像要下雪了。 3． as if从句中的省略。如果as if 引导的从句是“主语+系动词”结构，可省略主语和系动词等成份，这样as if 后就只剩下名词、不定式、形容词（短语）或动词-ing形式等。 He acts as if (he was) a fool. 他做事像个傻子。 He paused as if (he was going) to let the sad memory pass. The girl left the room hurriedly as if (she was) angry. 女孩匆忙离开房间，好像生气的样子。 From time to time, Jason turned round as if (he was) searching for someone. 词汇学习 1. A smelly gas came out of the cracks.
by的用法总结
by的用法小结： 1、介词prep. 在…旁；靠近 · Our teacher was sitting by the window. 我们的老师正坐在窗户旁边。 · Stand by me! 站到我的身旁来！ · We spent our holiday by the sea. 我们在海边度假。 2、介词prep. 经过 · He walked by me without speaking. 他走过我的身旁，没有说话。 · My brother goes by the building every day. 我弟弟每天从这楼旁走过。 3、介词prep. 用；靠；通过 using (showing who or what did something) · I know it by heart. 我把它记在心头。 · They can read by touch. 他们可以通过手摸来阅读。 · By getting up early, I can have an hour for reading English in the morning. 靠起得早，我每天早晨有一小时时间阅读英语。 4、介词prep. 不迟于 not later than · I shall be back by 5 o'clock. 最迟五点我一定回来。 · How many English parties had you had by the end of last term? 到上学期末，你们举行了几次英语晚会？ 5、介词prep. 通过；沿着 through; along; over
· We came through the fields, not by the road. 我们是穿过田野而不是沿那条路来的。· to send a letter by post 通过邮局寄信 6、介词prep. （表示作者）被；由 word that shows the author, painter, etc. · Thirty divided by two is fifteen. 三十除以二得十五。 · The child was saved by a PLA man. 这孩子是由一位解放军战士救活的。 · This bridge was built by the soldiers. 这座桥是士兵们造的。 7、介词prep. （指交通等）乘；用 word that shows what kind of transport, etc. · The man came by bus. 那人是坐公共汽车来的。 · They went to Shanghai by air. 他们坐飞机去上海。 8、介词prep. 在…情况下；在…时间during · Do you prefer travelling by day or by night? 你喜欢在白天还是在夜晚旅行？ 9、介词prep. （表示部分）在…部位word that shows which part · She led the child by the hand. 她拉着孩子的手往前走。 10、副词adv. 在旁边
初中英语介词用法归纳总结
初中英语介词用法归纳总结 常用介词基本用法辨析 表示方位的介词：in, to, on 1. in 表示在某地范围之内。 Shanghai is/lies in the east of China. 上海在中国的东部。 2. to 表示在某地范围之外。 Japan is/lies to the east of China. 日本位于中国的东面。 3. on 表示与某地相邻或接壤。 Mongolia is/lies on the north of China. 蒙古国位于中国北边。 表示计量的介词：at, for, by 1. at 表示“以……速度”“以……价格”。 It flies at about 900 kilometers an hour. 它以每小时900公里的速度飞行。 I sold my car at a high price. 我以高价出售了我的汽车。 2. for 表示“用……交换，以……为代价”。 He sold his car for 500 dollars. 他以五百元把车卖了。
注意：at表示单价(price) ，for表示总钱数。 3. by 表示“以……计”，后跟度量单位。 They paid him by the month. 他们按月给他计酬。 Here eggs are sold by weight. 在这里鸡蛋是按重量卖的。 表示材料的介词：of, from, in 1. of 成品仍可看出原料。 This box is made of paper. 这个盒子是纸做的。 2. from 成品已看不出原料。 Wine is made from grapes. 葡萄酒是葡萄酿成的。 3. in 表示用某种材料或语言。 Please fill in the form in pencil first. 请先用铅笔填写这个表格。They talk in English. 他们用英语交谈。 表示工具或手段的介词：by, with, on 1. by 用某种方式，多用于交通。 I went there by bus. 我坐公共汽车去那儿。 2. with表示“用某种工具”。
use用法总结
u s e用法总结 -标准化文件发布号：（9556-EUATWK-MWUB-WUNN-INNUL-DDQTY-KII
use的用法简单归纳如下： 1. used to do sth.意为"过去常常做某事"，它表示过去经常发生的动作或存在的状态，而现在已不再发生或存在。这个短语含有今昔对比之意，其否定形式常用used not to或didn't use to。反意疑问句中应该用did/didn't或used/usedn't。例如： I used to swim in this river when I was young.我年轻时常在这条河里游泳。 They used to be good friends, didn't they他们过去是好朋友，是吗？ 2. be used to sth. / doing sth.意为"习惯、适应某事/做某事"，它表示习惯于某一客观事实或状态，其中to是介词，后面跟名词、代词或动名词；be used可用于多种时态；如强调动作可用get或become替换be。例如： Old people are used to getting up early in the morning.老年人习惯早晨很早起床。 I wasn't used to city life, but now I have got used to living in this city.我以前不习惯都市生活，但现在我已习惯住在这座城市了。 3. be used to do sth.意为"被用来做某事"，其中use表"使用"之意，是被动语态形式，to是动词不定式符号。例如： Wood can be used to make paper.树木可以用来造纸。 4. be used for...意为"被当做……",其中use表"使用"之意，是被动语态形式。例如： The seal's fur can be used for coats.海豹皮可当做大衣用。 5. be of use意为"有用的"，其中use是名词，可用形容词来修饰。例如： The dictionary is of great use to the students.这本字典对学生们很有用。 6. be in use意为"在使用"，其中use也是名词。例如：
IF的用法
IF的用法 if是英语中出现频率很高的连词，并且它的用法也很多。学生感到很难掌握，为了让同学们更多更好地了解其用法及其语法功能。现结合教学中遇到的情况，予以归纳，以供参考。 一、if作为连词，引导条件状语从句，它表示的意思是“假如”“如果”等。在复合句中如果主句用将 来时，则if引导的状语从句用一般现在时。例如： 1. If itdoesn’train, we will go to the park next Sunday. 如果天不下雨，下周星期天我们将去公园。 2. If you ask him，he will help you．如果你求他，他将会帮助你。 二、if还可以引导让步状语从句。这时if当作“即使是”，“虽说”解。例如： 1. If she’s poor，at least she’s honest．虽说她很穷，但至少她还是诚实的。 2. If I am wrong，you are wrong，too．即使说我错了，那么你也不对。 3. I’ll do it, even if it takes me all the afternoon．虽然会花费我一下午的时间，我还是要做这事。 三、if作为连词还可以引导宾语从句。引导宾语从句时和whether意思相同。例如： 1. Lily asked if ／whether she liked it. 莉莉问她是否喜欢它。 2. She asked if ／whether they had a cotton one．她问是否他们有一件棉织的。 四、if引导时间状语从句，当if做“当”或“无论何时”解而不含有条件之义时，if从句中的时态与主句中的时态相同。例如： 1. If youmix yellow and blue，you get green．你将黄色与蓝色混合，便会得到绿色。 2. If she wants the servant，she rings the bell．每当她需要仆人时，她便按铃。 五、if后接否定动词，用于感叹句中，表示沮丧、惊奇等。例如： I. Well，if I haven’t left my false teeth at home!真倒霉，我把假牙丢在家里了! 2. And if he didn’t try to kn ock me down!(What do you think he did!He tried knock me down!)你猜他想做什么?他想把我撞倒! 六、用于虚拟语气中，if从句中用过去式，表示不可能实现，大概不会实现或提出作为考虑的假定条件。例如： 1. If you were a bird, you could fly.假使你是只鸟，你便会飞了。 2. If I asked him(if I were to ask him) for a loan，would he agree?如果我向他借贷，他会答应吗? 另外，if从句中用过去完成式，表示过去未实现的条件(例如由于不可能实现或某人之未能实行)。例如： 1. If they had startedearlier，they would have arrivedin time．要是他们早些动身，他们便可及时到达了。 2. If they had not started when they did，they would not be here now．如果他们那时不动身，现在他们就不会在此地了。 第三，在文学体栽中，if有时可省略，然后将主语与所用的限定动词(尤其是were，had，should)倒置。例如： 1. Should it (=if it should)be necessary，I will go. 倘若有必要，我会去的。 2. Were I(=if I were) in your place，I would do the same ．如果我处于你的位置，我也会这样干的。 3. Had I(=if I had)known earlier，I would come．如果我早一点知道，我就会来。 七、if与其它一些介词的连用。
(完整版)time的用法总结
一. time的短语 from time to time 有时 on time 准时寸,in time 及时寸; all the time 始终，一直; at the same time 同时, ahead of time 提前 at no time 绝不 some time 一段时间 sometime在某一时候”可用来指过去或将来 sometimes （at times, from time to time）有时，不时” at a time （a time）
at one time （once） at times ( sometimes) in no time (immediately ) 立刻，马上; have a good/nice time (enjoy on eself) 过的愉快 for the time being 暂时” “ Many a time/many times 多次 take one ' s time容 kill time消磨时间 【活学活用】选出与画线部分意思相同或相近的选项 1. Jim comes to visit us from time to time. That' always the happiest time for the family. A. on time B. sometime
C. at times D. some times 2．At no time ______ study though __ ___great progress. A. should we give up; we have made B. shouldn 'w t e give up; we have made C. we should give up; we have made D. we shouldn 'g t ive up; have we made 3. ---When shall we visit the Science Museum?” --- ________ next week. ” A. Sometime B. Sometimes C. Some time D. Sometimes 答案：1. C2.A 3A 二．time 相关从属连词高考常考点 1. every time / each time 每次Every time I call on him, he is out.
介词by用法归纳-九年级
页脚.
. . 教学过程 一、课堂导入 本堂知识是初中最常见的介词by的一个整理与总结，让学生对这个词的用法有一个系统的认识。页脚.
. . 二、复习预习 复习上一单元的知识点之后，以达到复习的效果。然后给学生一些相关的单选或其他类型题目，再老师没有讲解的情况下，让学生独立思考，给出答案与解释，促进学生发现问题，同时老师也能发现学生的盲点，并能有针对性地进行后面的讲课。 页脚.
. . 三、知识讲解 知识点1： by + v.-ing结构是一个重点，该结构意思是“通过……，以……的方式”，后面常接v.-ing形式，表示“通过某种方式得到某种结果”，即表示行为的方式或手段。 I practice speaking English by joining an English-language club. 我通过加入一个英语语言俱乐部来练习讲英语。 Mr Li makes a living by driving taxis.先生靠开出租车为生。 页脚.
. . 页脚. 介词by + v.-ing 结构常用来回答How do you...?或How can I...?之类的问题。 —How do you learn English? 你怎样学习英语呢？ —I learn English by reading aloud. 我通过大声朗读来学英语。 —How can I turn on the computer? 我怎样才能打开电脑呢？ —By pressing this button. 按这个按钮。 知识点2：by 是个常用介词，其他用法还有： 1【考查点】表示位置，意思是“在……旁边”，“靠近……”，有时可与beside互换。 The girls are playing by (beside) the lake. 女孩们正在湖边玩。 此时要注意它与介词near有所不同，即by 表示的距离更“近”。比较： He lives by the sea. 他住在海滨。 He lives near the sea. 他住在离海不远处。
英语中if的用法
精心整理1.(表示条件)如果,主句用将来时，if从句用现在时表示将来Hewillcomeifyouinvitehim. 如果你请他,他会来的。 2.(表示虚拟)假如,要是 1 a. b. 句型：条件从句主句 过去完成时should(would)have+过去分词 Ifshehadworkedharder,shewouldhavesucceeded. Thericewouldnothavebeenburntifyouhadbeenmorecareful.
IfmylawyerhadbeenherelastSaturday,hewouldhavepreventedmefromgoing. Ifhehadcomeyesterday,Ishould/wouldhavetoldhimaboutit. 含义：Hedidnotcomeyesterday,soIdidnottellhimaboutit. c. were+ Ifyousucceeded,everythingwouldbeallright. Ifyoushouldsucceed,everythingwouldbeallright. Ifyouweretosucceed,everythingwouldbeallright.
3.是否=whether连接宾语从句 Iwonderifsheisill. 不知她是否病了。 连接词conj. 1.( 2.( 3.( 4.是否 不知她是否病了。 5.(表示因果关系)每一次...的时候(总是会) IfIfeelanydoubt,Iinquire. 我一感到有疑问就随时询问。 if作为连词的时候，一般用于条件状语从句或者是宾语从句或让步状语从句
with用法小结
with用法小结 一、with表拥有某物 Mary married a man with a lot of money . 马莉嫁给了一个有着很多钱的男人。 I often dream of a big house with a nice garden . 我经常梦想有一个带花园的大房子。 The old man lived with a little dog on the lonely island . 这个老人和一条小狗住在荒岛上。 二、with表用某种工具或手段 I cut the apple with a sharp knife . 我用一把锋利的刀削平果。 Tom drew the picture with a pencil . 汤母用铅笔画画。 三、with表人与人之间的协同关系 make friends with sb talk with sb quarrel with sb struggle with sb fight with sb play with sb work with sb cooperate with sb I have been friends with Tom for ten years since we worked with each other, and I have never quarreled with him . 自从我们一起工作以来，我和汤姆已经是十年的朋友了，我们从没有吵过架。 四、with 表原因或理由 John was in bed with high fever . 约翰因发烧卧床。 He jumped up with joy . 他因高兴跳起来。 Father is often excited with wine . 父亲常因白酒变的兴奋。 五、with 表“带来”，或“带有,具有”，在…身上，在…身边之意
插入语用法归纳
插入语用法归纳 插入语用法很多,在句子中的位置比较灵活,在学习中应当认真去体会。大体而言,插入语可以分为以下几类: 1. 用简短的句子结构作插入语。这类短语有:I think, I hope, I guess, I believe, I suppose, I wonder, I tell you, I say, I'm afraid, I'm sure, you see, you know, as you know, that is, that is to say, what's more等等,它们可以置于句中或句尾。如: I suggest you choose someone who you think is kind and friendly. This diet, I think, will do good to your health. It won't be raining long, I hope. You will have to work harder, you know, if you want to succeed. 2. 副词或副词短语用作插入语,这类插入语一般放在句首或句尾。如: Happily for him, his father's second wife was kind to him too. You'll be able to pass the coming exam, surely. Luckily for him, he didn't hurt in the accident. Honestly, I don't need it at the moment. 3. 介词或介词短语作插入语,这类插入语一般放在句首,有时也可放在句中。如: Like most of my schoolmates, I have neither brothers nor sisters-in other words, I'm an only child. By the way, Bob sends his best wishes. On the other hand, I didn't know you were there. In short, things have begun to improve since schools were called on to reduce learning load. 4. 分词短语作插入语。如: Judging from your accent, you must be from England. Generally speaking, he is the best student in our class. Compared with China, the USA is smaller. 5. 不定式短语作插入语。如: To put it mildly, he was not up to the mark. To tell you the truth, I don't want to see her. To be sure, Jim is a faster skater, but he is not good at doing figures. To conclude, it was a great success. 在日常交际用语和书面表达中，插入语频频出现。英语中的插入语（Parenthesis）是插在句子中的一个词，短语或从句，通常被逗号、破折号或句子的其他部分隔开，它与句子的其他部分之间没有语法上的关系，因此，有的语法学家将其归为独立成分。 插入语在句中通常是对一句话的一些附加解释，说明或总结；有时表示说话者的态度和看法；有时起强调的作用；有时是为了引起对方的注意；还可以起转移话题或说明事由的作用；也可以承上启下，使句子与前面的语句衔接的更紧密一些。 插入语大致可分为以下10种类型： 1. 形容词或形容词短语作插入语
if用法归纳
1. If you eat my food, I won’t talk to you. (P58) 2. I will die , I don’t have food, (P58) 3. What shall we do if it rains tomorrow? 5. She asked me if I was fond of music. 她问我是否喜欢音乐。 6. Can you tell me if they’re planning to come? 你能告诉我他们是否打算过来吗？ 7. I don’t know if she’s coming. 我不知道她是否会来。 ◇相关词组 ☆if you want/like如果你愿意的话 You can come and stay with us if you want. ☆if so如果是的话 Are you planning to return to work, and if so, who is going to look after the baby? ☆if not如果不是的话 Has anyone dealt with the technical problems? And if not, why not?☆if necessary/if possible 如果必要/可能的话 We are ready to fight for our rights if necessary. I should like to be back here by 10:30 if possible. ☆even if即使 I’d rather never sell this painting, even if they offered me a million dollars. ☆what if 要是……，那怎么办？如果……那会怎样？ What if the boss walked in here now and saw us? ☆as if好像是…… She always talks to me as if she was my sister. ◇相关练习 动词填空： 1. If it ______ (be) sunny tomorrow, I ______( walk) to school . 2. We ________ (not have ) our sports meeting if the
to 用法总结
be/get/become used to 习惯于 be related to 与…有关系 be addicted to 沉溺于；对…上瘾 be opposed to 反对 devote oneself to献身于；专心于 be devoted to 致力于；忠诚于 be admitted to 被…录取；准进入 be reduced to 沦为 reduce…to…使…沦为 be attached to附属于；喜欢；依恋 be adjusted to 适应 be sentenced to被判处 be exposed to 暴露于；遭受 be/become/ get accustomed to//accustomed to 惯于；有…习惯be engaged to 与…订婚 get down to 着手做 lead to 导致 object to反对；不喜欢；不赞成 give rise to 引起 stick to 坚持； see to 负责；注意 contribute to对…作贡献；有助于 make contributions to对…作贡献 apply oneself to 致力于 in addition to除…之外 turn to转向；求助于 look up to 尊敬 belong to 属于 take to 喜爱；开始 respond to 回答；对…作出回应 amount to等于 refer to 谈到；参考；查阅 turn a blind eye to对…视而不见 turn a deaf ear to 对…充耳不闻 show honour to向…表示敬意 propose a toast to 提议…… set fire to 放火烧…… occur to sb. 想起；想到 hold to 坚持；抓住 help oneself to 随便用…… hold on to 抓住；固守
疑问代词用法总结归纳
疑问代词用法总结归纳 以下是为大家整理的疑问代词的用法总结，希望能帮助大家更好地认识疑问代词，提高英语水平。 1) 疑问代词在句中起名词词组的作用，用来构成疑问句。疑问代词有下列几个： 指人：who, whom, whose 指物：what 既可指人又可指物：which 2) 疑问代词在句中应位于谓语动词之前，没有性和数的变化，除who之外也没有格的变化。what, which, whose还可作限定词。试比较： 疑问代词：Whose are these books on the desk? 桌上的书是谁的? What was the directional flow of U. S. territorial expansion? 美国的领土扩张是朝哪个方向的? 限定词：Whose books are these on the desk? 桌上的书是谁的? What events led to most of the east of the Mississippi River becoming part of the United States?哪些事件使密西西比
河以东的大部分土地归属于美国? 说明1： 无论是做疑问代词还是限定词，which 和what 所指的范围不同。what所指的范围是无限的，而which则指在一定的范围内，例如： What girls do you like best? 你喜欢什么样的姑娘? Which girls do you like best? 你喜欢哪几个姑娘? 说明2： Whom是who的宾格，在书面语中，它作动词宾语或介词宾语，在口语中作宾语时，可用who代替，但在介词后只能用whom, 例如： Who(m) are you taking the book to? 你要把这书带给谁?(作介词宾语，置句首) Who(m) did you meet on the street? 你在街上遇到了谁?(作动词宾语) To whom did you speak on the campus? 你在校园里和谁讲话了?(作介词宾语，置介词后，不能用who 取代。) 说明3： 疑问代词还可引导名词性从句，例如：
if、 whether 用法总结
whether,if if和whether通用，都表示“是否”的意思。一般来说，后者比较正式，在口语中前者常用来代替后者。但两者有时具有不同的暗示。用whether时，正反两面的选择意义较强，问话人并不在意回答是肯定还是否定；而用if时，则比较强调单方面，即正面，问话人希望得到肯定的回答。另外，还要注意以下几点： 一、whether和if都可以与or not连用；但写在一起时，只能用whether，不能用if。如： I don't care whether (或if) it will rain or not． I don't care whether or not it will rain. (不用if) 二、在引导宾语从句时，应注意： 1、表示“是否”时，两词都能引导宾语从句。 I wonder if/whether you can examine him now． 2、宾语从句移置句首时，用whether，不用if。
Whether it is true or not，I can't say． 3、宾语从句为否定形式时，通常用if，而不用whether。 I asked Tom if Mary wouldn’t come． 4、作discuss等词的宾语，用whether不用if。 We discussed whether we should buy the gift for him． 三、在下列情况下，只能用whether，不能用if。 1、与不定式连用时，只能用whether． He can't decide whether to accept or refuse． 2、在介词后，只能用whether。 Everything depends on whether he is ready． 3、在名词后作同位语时，只能用whether。
的用法总结
I t的用法总结 一. 代词: 1)指代上文 2)指代this/that 3)指代未知性别的婴儿或孩子或身份不明的人 4）指代时间/地点/天气/温度/距离/环境 1.It gets dark very early in the winter. 2.What will you call it if it’s a boy 3.I love spring---It’s a wonderful time of the year. 4.It’s less than 100 kilometres from here to Jinan. 5.When the factory closes, it will mean 500 people losing their jobs. 6.What’s this It’s a cat. 7.It has snowed much this year. (1)The book in your bag is very interesting. Can I borrow (2) The book in your bag is more interesting than ______ on the desk. (3) The weather here is much colder than____ in Nanjing. (4) The books are free. You can take____ free of charge. (5) The books in the bag are better than _____ on the desk.
英语中一些重点词的用法归纳总结
since的用法：译作“自从…以来” (1)接时间点：如 I have stayed in that country since 1995.要求：谓v.用现在完成时,而且须是延续性动词. (2)接一段时间 + ago：如 They have lived in that house since two years ago.要求：谓v. 用现在完成时,而且须是延续性动词. (3)接时间状语从句：如 I have loved her since I met her last time./ Lily has stayed at home since she left school.要求：主句的谓v.用现在完成时,而且须是延续性动词；从句的谓v.用一般过去时,而且须是终止性动词. (4)用于句型“It’s / It has been + 一段时间 + since + 时间状语从句”中,译作“自从… 以来,已经…(时间)了”.如 It’s / has been three months since he moved to this city.要求：主句的谓v.用一般现在时或现在完成时；从句的谓v.用一般过去时,而且须是终止性动词. (5)用于句型“一段时间 + has passed since + 时间状语从句”中,译作“自从…以来,… (时间)已经过去了”.如上个例句还可写成：Three months has passed since he moved to this city.要求：主句的谓v.用现在完成时,而且动词必须是has passed；从句的谓v.用一般过去时,而且须是终止性动词. (6)注：当since用于否定句时,主句的谓v.可以是终止性动词.如 He hasn’t seen the film since last month. (7)相关词组：“从那时起”：ever since、since then、from then on. 注：ever since作为一个词组,放句尾可单独使用.如I have given up smoking ever since.另外,还可在since后接句子.since前加ever,只是加重语气而已.如 I have given up smoking ever since I caught a bad cough. (8) since还可引导原因状语从句,译作“由于；因为”,相当于because.如 Since he was lazy,he didn’t finish his homework.
详细版if的用法.doc
一、if作为连词，引导条件状语从句，它表示的意思是“假如”“如果”等。在复合句中如果主句用将来时，则if引导的状语从句用一般现在时。例如： 1. If itdoesn’train, we will go to the park next Sunday. 如果天不下雨，下周星期天我们将去公园。 2. If you ask him，he will help you．如果你求他，他将会帮助你。 二、if还可以引导让步状语从句。这时if当作“即使是”，“虽说”解。例如： 1. If she’s p oor，at least she’s honest．虽说她很穷，但至少她还是诚实的。 2. If I am wrong，you are wrong，too．即使说我错了，那么你也不对。 3. I’ll do it, even if it takes me all the afternoon．虽然会花费我一下午的时间，我还是要做这事。 三、if作为连词还可以引导宾语从句。引导宾语从句时和whether意思相同。例如： 1. Lily asked if ／whether she liked it. 莉莉问她是否喜欢它。 2. She asked if ／whether they had a cotton one．她问是否他们有一件棉织的。 四、if引导时间状语从句，当if做“当”或“无论何时”解而不含有条件之义时，if从句中的时态与主句中的时态相同。例如： 1. If youmix yellow and blue，you get green．你将黄色与蓝色混合，便会得到绿色。 2. If she wants the servant，she rings the bell．每当她需要仆人时，她便按铃。 五、if后接否定动词，用于感叹句中，表示沮丧、惊奇等。例如： I. Well，if I haven’t left my false teeth at home!真倒霉，我把假牙丢在家里了! 2. And if he didn’t try to knock me down!(What do you think he did!He tried knock me down!) 六、用于虚拟语气中，if从句中用过去式，表示不可能实现，大概不会实现或提出作为考虑的假定条件。例如： 1. If you were a bird, you could fly.假使你是只鸟，你便会飞了。 2. If I asked him(if I were to ask him) for a loan，would he agree?如果我向他借贷，他会答应吗? 七、if从句中用过去完成式，表示过去未实现的条件(例如由于不可能实现或某人之未能实行)。 1. If they had startedearlier，they would have arrivedin time． If they had not started when they did，they would not be here now． 第三，在文学体栽中，if有时可省略，然后将主语与所用的限定动词(尤其是were，had，should)倒置。例如： 1. Should it (=if it should)be necessary，I will go. 倘若有必要，我会去的。 2. Were I(=if I were) in your place，I would do the same ． 3. Had I(=if I had)known earlier，I would come．如果我早一点知道，我就会来。 八、if与其它一些介词的连用。 （1）as与if连用，它的意思是：“仿佛、好像”同样引导从句。例如： 1. It isn’t as if we are rich．(We are not rich．)我们不像富有的样子。(即我们不富有) 2. It isn’t as if he doesn’t know the ruler．(i．e．He does know the rulers．) （2）as if还可以引导感叹句。例如： As if I would allow it!(i．e．I would certainly not allow it!) （3）if与only连用。常表示愿望或一个未实现的条件，尤其用于感叹句中。例如： 1. If only he arrives in time!他若能及时到达就好了! 2. If only she would marry me!但愿她能嫁给我！ 3. If only she had known about it!（But she didn’t know.） 1.if 可引导状语从句----“如果...,假使...”[就现在,过去,未来可能实现之事加以推测时] If you are tired, we will go straight home 如果你疲倦了,我们就直接回家 If you have finished reading this book, please return it to me Do you mind if I open the window? 如果我打开窗子,你介意吗?