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before和since区别精品PPT课件

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since的用法课件

since的用法课件
since的用法课件
目录
• since的基本含义 • since的常见用法 • since的特殊用法 • since的常见错误用法 • since的练习与巩固
01
since的基本含义
翻译与解释
01
自从
since可以翻译为“自从”，表示某个时间点或时 间段之前的时间。
02
因为
since还可以翻译为“因为”，表示原因或理由。
与过去完成时连用
总结词
表示某个动作或状态在过去的某个时间点之前已经完成，强调过去的某个时间点之前的 状态。
详细描述
当与过去完成时连用时，since表示某个动作或状态在过去的某个时间点之前已经完成， 并且强调那个时间点之前的状态。这种用法通常与过去完成时态（had done）等连用， 表示在过去的某个时间点之前已经完成了某个动作或状态。例如：“He had left the
since的特殊用法
与完成时态连用
总结词
表示某个动作或状态从过去某时开始一 直持续到现在，强调现在的结果或影响 。
VS
详细描述
当与完成时态连用时，since表示某个动作 或状态从过去某时开始一直持续到现在， 并且强调现在的结果或影响。这种用法通 常与现在完成时态（have done）或过去 完成时态（had done）等连用，表示动作 或状态已经完成，并且持续了一段时间。 例如：“I have lived in this city since 2010.”（我从2010年开始就住在这个城 市。）
填空题练习
填空题1
I _______ (not see) her since last week.
填空题3
He _______ (not live) here since he left the city.

before／ago,since用法

before／ago,since用法

before和ago都能表示在一段时间以前，但是二者的内涵和具体用法有明显的区别：1. before表示从过去或将来某一时间算起多少时间以前，由于与这一时间状语连用的行为先发生在过去或将来某一时刻之前，因此往往出现在过去完成时态或将来完成时态中。

例如：①I called him up last night，but his mother told me he had left for Wuhan two days before.②She said that she had married him five years before.2.如果不具体表明多少时间以前，before意为"从前；以前"，表示从现在开始追溯到过去一段时间，或者主句的谓语动词表示的是经常、反复发生的行为，以副词的形式置于句末，可以用在现在完成时态中。

例如：①I have never been to Beijing before.②Have you ever seen a tiger before?③I often go over the lessons that I have learned a few days before.注意：before前的时间状语如果是特定的，含义不一样。

试比较：He said he had arrived here a day before. (一天前)He said he had arrived here the day before. (前一天)3. ago指的是从现在起到过去时间的某一点的一段时间。

这个时间状语常与一般过去时态或过去进行时态连用。

例如：①I graduated from the college twenty years ago.②I was asked what I was doing a month ago.4. 表示在某一时间点或事件以前时，只能用before，不用ago。

it+be+时间+before,since,when从句 课件

it+be+时间+before,since,when从句 课件
It +be +时间+ before/since/when 从句
1. It is / has been + 一段时间 + since从句
如：It is 17 years since Hongkong returned to China.
香港回归已经有17年了。
在“It’s +时间段+ since从句” 句型中，如果since从句的谓语动 词是瞬间性动词，表示肯定意义； 如果since从句的谓语动词是延续
了多长时间之后才……” 例： It was long before they found their son. 过了很久他们才找到他们的儿子。
② 若主句是否定形式，翻译成 “没过多久就……” 例：
It was not long before the couple met again. 没过多久这对夫妻就见面了。
分析：since从句中的系表结构表示 一种状态，这种状态是延续性的， 表示否定意义，译为“不是，不当”
注：时间的计算一律从since从句 的动作完成或状态结束时算起。
It is/has been two days since she fell ill. (她生病两天了） It is/has been two days since she was ill.
5. It was midnight _w__h_e_n___ he arrived home. 6. It was at midnight __t_h_a_t___ he
7a.rIrtivweadshnoomt eu.ntil midnight _t_h_a_t___ he arrived home.
强化习题：
ቤተ መጻሕፍቲ ባይዱ

详解before用法(课堂PPT)

详解before用法(课堂PPT)
We didn’t wait long before he came back. 我们没等多久他就回来了。 9
5． before表示“与其……宁可……，比……优先”(用于表优 先顺序)
例5： They would fight to death_____ they surrendered(投降)．
A. before B. after C. since D. because 解析： 答案为A。before引导的从句在与will, would连
4
2． before表示“不知不觉，还没弄清 就……”(常用于before sb. know／ realize…)
例2： Several weeks had gone by_____ I realized the painting was missing. (2004全国) A. as B. before C. since D. when
平洋航行了两个星期才回到家。”强调从句动作比主句动 作发生晚。又如：
I thought carefully about it before I made a decision. 我经过再三考虑才决定situation improves. 或许要过很多年这种状况才能得到改善。
2
1． before表示“不等……就……”、“尚未……就 ……”
例1： —Why didn’t you tell him about the meeting？ (2006年四川)
—He rushed out of the room_____ I could say a word.
A. before B. until C. when D. after 解析：答案为A。题中before意为“不等……就 ”、“尚未……就……”，它表示从句的动作尚未来得 及发生，主句的动作已发生或完成。全句句意为：

2023年中考英语复习状语从句(条件、时间) 复习课件27张PPT

2023年中考英语复习状语从句(条件、时间) 复习课件27张PPT
❖ 4.If everyone___co_m__e_s（come）to the restaurant,the restaurant will be too crowded.
❖ 5.If Jack__p_a_s_s_e_s（pass）the entrance examination of the college,he will go to Beijing.
• 1.You can’t improve your spoken English ____ you practice itBeveryday from now on.
• A. as soon as B. unless C. if D. since
• 3.They__w__o_n_’_t_l_e_a_v_e（not leave）their classroom until the bell__r_i_n_g_s_（ring）
• 4.As soon as the police__fi_n_d__s（find）him, they
will take him home.
词的用法。
一、状语从句的概述
❖ 在复合句中修饰主句中的动词、形容词或副 词等，充当状语的成分，那么这个句子就叫 做状语从句。
❖ 状语从句通常由连接词或词组引导。从句位 于句首或句中时通常用逗号与主句隔开，位 于句尾时可以不用逗号隔开
❖ 二、时间状语从句
❖ 时间状语从句用来表示主句动作发生的时间。
❖ 引导时间状语从句的连接词有：when(while, as)当……时候； before在……之前；after在……之后；since自从；until/till直 到；as soon as一……就。
❖ 1. when(while, as) ❖ 表示主句与从句的动作同时发生。 ❖ 【例句】 ❖ Tom will go to see you when he has time. 汤姆有

It…sincebeforethat混淆句型PPT课件

It…sincebeforethat混淆句型PPT课件

still remember the scene ______ we got
separated on a rainy day.
A. before; where
B. before; which
C. since; when
D. since; where
6.—Did Jack come back early last night? —Yes.It was not yet eight o'clock ______ he arrived home.
8.How long do you think it will be___China sends a manned spaceship to the moon? A. when B.until C.that D.before
4
虚拟类
Richard __________ injured in the car crash ，but I didn’t stop him driving after he drank some beer． A．wouldn’t have got B．might not get C．mustn’t have got D．should not get
A. before B. when C. that D. until 3
7.It was a long time ________ the miners in Chile were rescued from under the mine. A. until B. when C. before D. since
7
结束语
当你尽了自己的最大努力时，失败也是伟大的， 所以不要放弃，坚持就是正确的。
When You Do Your Best, Failure Is Great, So Don'T Give Up, Stick To The End

中考英语二轮复习语法专项：状语从句课件(32张PPT).ppt


目的 so that (以便, 为了), in order They sped up so that/ in
状语从句 that (为了)
order that they could get
there on time.
分类
引导词
例句
结果 so … that / such … that (如 It’s so hot that nobody
在主从复合句中作状语的从句叫做状语从句。状语从 句由从属连词引导，与主句连接，位于句首时，常用逗号 与主句分开，位于句末时，其前一般不用逗号。
状语从句根据其用途可分为时间状语从句、条件状语 从句、原因状语从句、目的状语从句、结果状语从句、让 步状语从句、比较状语从句、地点状语从句等。
分类
引导词
例句
A. so
B. when
C. unless
( A )2. I love to listen to rock music _______ I am running.
A. while
B. after
C. since
D. until
( B )3. Ann didn't know anything about the news _______
状语从句 此……以至于)
wants to go out.
though/although (尽管, 虽然), Although milk is good，
让步 even though/if (即使),
状语从句
whatever (无论什么), whenever (无论何时),
you should not drink too much of it. Whatever you want to be,

初中全新英语语法——状语从句(共19张PPT)

He is absent, because he is ill.(“生病”是“缺席”的 必然原因)
The swimming pool won't be open today because t hey're making repairs.
— Why did you move to France?
—Because my father found work in Paris.
条件状语从句
(1)if引导条件状语从句
if引导条件状语从句意为如果”，表示一种假设的条 件。如：
You can leave now if you like.如果你愿意现在就 可以走了。
If you study hard, you will pass the final examination.
(2) unless引导条件状语从句
地点状语从句
1. where引导地点状语从句 where引导地点状语从句表示“......的地方”。 We live where the road crosses the river. 2.wherever引导地点状语从句 wherever引导地点状语从句意为“在......的任何(所 自)地方”。如： You can sit wherever you like. You can put the book where you like.
You should do as I told you.
You must try to hold the tool as I do.
Just as we sweep our rooms，so we should sweep backward ideas from our minds.
比较状语从句

(完整word版)since,before,when,after等的区别

高考英语常考句式——it is +时间+ since (before, when)…请注意以下三个句式的区别和意思上的差异（其中的 is 根据情况可以有其他时态形式）：It is + 时间段 + since…的意思是“自从……以来有一段时间了”。

It is + 时间点 + when…的意思是“当……的时候时间是……”。

It is + 时间段 + before…的意思是“在……之前有一段时间”。

请看以下用例：It’s ten years since they got married. 他们结婚到现在已经十年了。

It was past one o’clock when he came in. 他回来时已经一点多了。

It won’t be long before they understand each other. 过不了多久他们就会互相了解的。

有时翻译可以比较灵活：It’s a long time since I met you last. 好久不见了。

(直译：自上次见到你以来有很长一段时间了。

)It’s about three years since I last played basketball. 我差不多有三年没有打篮球了。

(直译：自从我上次打篮球以来已差不多有三年了。

)请看有关高考题(答案为DDBCDC)：1.That was really a splendid evening. It’s years _________ I enjoyed myself so much. (安徽卷)A.whenB.thatC. beforeD.since2.It was some time _________we realized the truth. (山东卷)A.whenB.untilC.s inceD.before3.—Did Jack come back early last night?—Yes. It was not yet eight o’clock _________he arrived home. (福建卷)A.beforeB.whenC.thatD.until4.Scientists say it may be five or six years _________it is possible to test this medicine on human patients. (福建卷)A.sinceB.afterC. beforeD.when5.It was evening we reached the little town of Winchester. (天津卷)A.thatB.untilC.sinceD.before6.It _________ long before we _________ the result of the experiment. (上海春)A.will not be; will knowB.is; will knowC.will not be; knowD.is; know【全真模拟训练】1.It was about midnight _________ we found the lost child, crying under a tree.A.thatB.until C .when D.where2.It's some time _________ I have spoken to you about this matter.A.thatB.unlessC.si nceD.until3.It was ten _________ he stood at aunt’s door and rang the bell.A.whenB.untilC.sin ceD.that4.I think it won’t be long _________ they understand each other.A.whenB.untilC.sin ceD.before5.How pleased I am tonight! It’s years _________ we had so great a time together.A.whenB.thatC.be foreD.since6.It was some time _________ we realized how important the matter is.A.whenB.untilC.sin ceD.before7.—Did you come home very late last night?—No. It was just half past seven _________ I appeared before my parents.A.thatB.whenC.un tilD.since8.How time files! It seems like years _________ I last saw you.A.whenB.thatC.si nceD.before9.It’s more than half a century _________ the People’s Republic of China was liberated.A.whenB.thatC.si nceD.after答案：1—5 CCADD 6—9 DBCCwhen〔引导时间状语从句〕具体地说，它有以下几种含义：1．表明一个动作发生的时候，另一个动作正在进行之中。

since,before,when,after等的区别

高考英语常考句式——it is +时间 + since (before, when)…请注意以下三个句式的区别和意思上的差异（其中的 is 根据情况可以有其他时态形式）：It is + 时间段 + since…的意思是“自从……以来有一段时间了”。

It is + 时间点 + when…的意思是“当……的时候时间是……”。

It is + 时间段 + before…的意思是“在……之前有一段时间”。

请看以下用例：It’s ten years since they got married. 他们结婚到现在已经十年了。

It was past one o’clock when he came in. 他回来时已经一点多了。

It won’t be long before they understand each other. 过不了多久他们就会互相了解的。

有时翻译可以比较灵活：It’s a long time since I met you last. 好久不见了。

(直译：自上次见到你以来有很长一段时间了。

)It’s about three years since I last played basketball. 我差不多有三年没有打篮球了。

(直译：自从我上次打篮球以来已差不多有三年了。

)请看有关高考题(答案为DDBCDC)：1. That was really a splendid evening. It’s years _________ I enjoyed myself so much. (安徽卷)A. whenB. thatC. beforeD. since2. It was some time _________we realized the truth. (山东卷)A. whenB. untilC. sinceD. before3.—Did Jack come back early last night?—Yes. It was not yet eight o’clock _________he arrived home. (福建卷)A. beforeB. whenC. thatD. until4. Scientists say it may be five or six years _________it is possible to test this medicine on human patients. (福建卷)A. sinceB. afterC. beforeD. when5. It was evening we reached the little town of Winchester. (天津卷)A. thatB. untilC. sinceD.before6. It _________ long before we _________ the result of the experiment. (上海春)A. will not be; will knowB. is; will knowC. will not be; knowD. is; know【全真模拟训练】1. It was about midnight _________ we found the lost child, crying under a tree.A. thatB. untilC. whenD. where2. It's some time _________ I have spoken to you about this matter.A. thatB. unlessC. sinceD. until3. It was ten _________ he stood at aunt’s door and rang the bell.A. whenB. untilC. sinceD. that4. I think it won’t be long _________ they understand each other.A. whenB. untilC. sinceD. before5. How pleased I am tonight! It’s years _________ we had so great a time together.A. whenB. thatC. beforeD. since6. It was some time _________ we realized how important the matter is.A. whenB. untilC. sinceD. before7.—Did you come home very late last night?—No. It was just half past seven _________ I appeared before my parents.A. thatB. whenC. untilD. since8. How time files! It seems like years _________ I last saw you.A. whenB. thatC. sinceD. before9. It’s more than half a century _________ the People’s Republic of China was liberated.A. whenB. thatC. sinceD. after答案：1—5 CCADD 6—9 DBCCwhen〔引导时间状语从句〕具体地说，它有以下几种含义：1．表明一个动作发生的时候，另一个动作正在进行之中。

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写在最后
经常不断地学习,你就什么都知道。你知道得越多,你就越有力量 Study Constantly, And You Will Know Everything. The More
You Know, The More Powerful You Will Be
谢谢大家
荣幸这一路，与你同行
It'S An Honor To Walk With You All The Way
before long “很快，不久” 各种时态
long before “很久以前” 一般用在过去时或过去完成时 例如： ① Before long, he went to America. 不久他就去了美国。
I hope to see you before long. 我希望不久后再见到你。 ②She said she had read the novel long before. 她说她很久以前就读过这部小说。
自从来到我们学校， 他学习就非常努力。
Great changes have taken place in our school since you left.
自从你离开这里， 我们学校发生了很大的变 化。
(2) 若since引导的状语从句的谓语动词是持续性动词或 表示状态的静态动词(如live， stay， study， learn， smoke， be等)的过去时， 则从句表示的时间是“从 该动作或状态的完成或结束时算起”。如：
2． 用于It + be + 时间段 + before...句型中，意思是 “在……之后才……”。例如： It will be five years before I come back. 我五年后才能回来。 It was not long before the enemy was driven out of their country. 不久之后，敌人就被赶走了。 如果主句中用否定式，则表示“不多久……就”。 It won’t be long before they understand each other. 他们不久就会互相了解的。
before用法
一、 before用作连词 (3)
1． before用作连词时，意思是“在……之前；还没来得 及 …… 就”。例如：
Before I could say a word, she had rushed out of the room. 不等我说一句话，她就冲出了房间。
Don’t count your chickens before they are hatched. 不要 高兴得过早。
He got a job with the firm in 1970 and has worked there ever since. 他从1970年开始在那家公司任职， 之后就一 直在那里工作。
三.用作连词
1. 引导原因状语从句，相当于now that，意思是 “因为……，既然……， 鉴于……”。
演讲人：XXXXXX 时 间：XX年XX月XX日
Since the rain has stopped, let's go for a walk.
既然雨停了， 我们出去散散步吧。
Since we are young， we shouldn't be too afraid of making mistakes.因为我们还年轻， 所以不应该太害怕犯错误。
That happened long before. 那件事发生在很久以前。
Since 的用法
一.用作介词， 意思是“从……以来， 自从”， 常与完成时连用。
I haven‘written home since Christmas
自圣诞节以来， 我未曾写信回家。
二.用作副词，意思是“从那时以后(一直到现 在)”， “其后(到现在之间)”; ever since从那以 后一直 (更加强调since的用法)。
用法注意：since从句中常用一般过去时，若 从句中是持续性动词的一般过去时， 则表示 该动作结束有多长时间了。
It is three years since he smoked.
他不吸烟已有3年了。
注意：在这种结构中， since引导的从句绝对不 能用否定式的谓语动词来表示否定意义
翻译 ： 他好久没学汉语了。
2. 引导时间状语从句，此用法较复杂。
(1) 若since引导的状语从句的谓语动词是 终止性动词(如go，come，leave， start， begin等)的过去时， 则从句表示的时间是“从 该动作开始的那一时刻起”。
He has studied very hard since he came to our school.
3． 还有“趁……（还没有）”之意。 例如：
They are thinking of buying the house before the prices go up. 他们正在考虑趁房价 未涨时把房子买下来。
Do it before you forget it. 趁早动手，以免 忘了。
before long与long before的区别 do you know???
Things have not changed very much since. 从那时起， 情况并没有太大的改变。
His first book was a great success and he has been famous as a writer ever since. 他的第一本书非常畅销， 从那时起他就成了 一位名作家。
I haven't heard from him since he lived here. 从他不住这儿起， 我一直没有收到他的信。
It' a two years since he was a soldier. 他退役有两年了。
(4) It is + 一段时间 + since... / It has been + 段时间 + since...表示“从……起已有多长时 间了”。