状语从句课件
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初中英语状语从句课件(共68张ppt)
They had not been married four months before they were divorced. 他们结婚还不到四个 月就离婚了。
After you think it over, please let me know what you decide.你仔细考虑过以后，告诉我你是 怎样决定的。
外星人买纪念品时，那女孩给警察打了电话。(表示主句，从句
的动作同时发生，while后引导的状语从句的动词必须是延续动词不能
是点动词，因为它表示较长时间)
mother was worried because little alice was ill, especially as (when/ while) father was away.
我到那里时，正在下大雨。 ( 动作同时发生，when
可换为as, 但不能换为while，因为get是点动词.)
When I had read the article, he called me.
我看完这篇文章之后，她给我打了电话。( 从句动作
发生在主句之前，注意时态表达，只能用when )
When I got to the cinema, the film had begun.
when
1、还可以表示从句动词的动作在主几句动词的动作"
之前 "或"之后"发生。
2、when=and then; at that moment (正在那个时候)
while 1、用于时间较长时
2、 强调两个动作同时进行，并表示对比时
有时这三个连词可以互换，有时不可以。
It was raining hard when (as) I got there.
After you think it over, please let me know what you decide.你仔细考虑过以后，告诉我你是 怎样决定的。
外星人买纪念品时，那女孩给警察打了电话。(表示主句，从句
的动作同时发生，while后引导的状语从句的动词必须是延续动词不能
是点动词，因为它表示较长时间)
mother was worried because little alice was ill, especially as (when/ while) father was away.
我到那里时，正在下大雨。 ( 动作同时发生，when
可换为as, 但不能换为while，因为get是点动词.)
When I had read the article, he called me.
我看完这篇文章之后，她给我打了电话。( 从句动作
发生在主句之前，注意时态表达，只能用when )
When I got to the cinema, the film had begun.
when
1、还可以表示从句动词的动作在主几句动词的动作"
之前 "或"之后"发生。
2、when=and then; at that moment (正在那个时候)
while 1、用于时间较长时
2、 强调两个动作同时进行，并表示对比时
有时这三个连词可以互换，有时不可以。
It was raining hard when (as) I got there.
状语从句(43张PPT)初中英语专项复习课件
知识点 2 状语从句的连接词
(3) 强调句型：It is/was not until ... that ...
It was not until the professor came that we began the experiment. 直到教授来了，我们才开始做实验。 易错点：（1）till不可以置于句稿首定，PP而T until可以。 Until you told me I had no idea o稿新f定，itP上.P千T，款海模量板素选材择持总续有更一 直到你告诉我，我才知道这件事款适。合你
It’s three years since he joined the army.(自从......多久了......)
自从他参军已经三年了。
稿定PPT
稿定PPT，海量素材持续更
It's two years since we arrived新h，e上re千. 款我模们板选到择这总有儿一两年了。 款适合你
连词
常用句式
before It will be＋一段时间＋before ... 过……时间才……
since
It will not be/was not long＋before ... 不久就会/没多久就…… It was＋时间段＋befo稿稿r定e定P.P.P.TP，过T海了量素…材…持续(时更 间)才…… It is/has been＋一段时新间，上＋千s款in模c板e选..择. 总(从有一句用一般过去时)
as soon as / no sooner … than / hardly … when / the moment / the minute /（一…就…) since （自从…以来）
知识点2：状语从句的连接词 No. 1 时间状语从句 1．when, while, as 引导的时间状语从句
高中英语语法复习课件--状语从句(48张PPT)
keep it clean.
• * in case(万一） • Send us a message in case you have any
difficulty.
• *on condition that（？） • We’ll let you use the room on condition
that you keep it tidy.
• for 解释说明 • He must be ill, _______.(因为他今天没来)
三 条件状语从句 conditional adverbial clause
if,unless,so/as long as, in case on condition that, provided that,providing that,suppose that, supposing that
if If you work harder,you will succeed.
unless :if... not 除非 • Unless he comes, we won’t be able to go. • If he doesn’t come,we won’t be able to go.
• * as/so long as(只要 ) • You may borrow the book as long as you
2. while“尽管，虽然”，相当于although
3. while意为“而，却”，表示对比。 Jane was dressed in brown while Mary was dressed in blue.
as的用法
1. “一边…一边”； “随着” She was doing her homework as she was listening to the music.
• * in case(万一） • Send us a message in case you have any
difficulty.
• *on condition that（？） • We’ll let you use the room on condition
that you keep it tidy.
• for 解释说明 • He must be ill, _______.(因为他今天没来)
三 条件状语从句 conditional adverbial clause
if,unless,so/as long as, in case on condition that, provided that,providing that,suppose that, supposing that
if If you work harder,you will succeed.
unless :if... not 除非 • Unless he comes, we won’t be able to go. • If he doesn’t come,we won’t be able to go.
• * as/so long as(只要 ) • You may borrow the book as long as you
2. while“尽管，虽然”，相当于although
3. while意为“而，却”，表示对比。 Jane was dressed in brown while Mary was dressed in blue.
as的用法
1. “一边…一边”； “随着” She was doing her homework as she was listening to the music.
《状语从句用法详解》课件
结果状语从句
意义解析
解释结果状语从句的含义， 强调其与主句的关系。
论证方法
介绍一些常用的论证方法， 包括通过结果状语从句来支 持自己的观点。
举例说明
给出一些具体的实例，让学 生在理解中应用结果状语从 句。
3
展示效果
展示一些有趣的例句和图片，展示时间状语从句在实际应用中的魅力。
地点状语从句
定位信息
介绍地点状语从句的作用和使 用场景，通过例句帮助学生理 解。
举例说明
提供实际案例，讲解地点状语 从句如何在具体的句子中发挥 作用。
பைடு நூலகம்
练习任务
让学生完成一些任务，包括填 空、转述等，以加深他们对地 点状语从句的理解和应用。
方式状语从句
1 定义和示例
用简洁的语言解释方式状 语从句的含义，并给出具 体的例子帮助学生理解。
2 练习和提醒
设计一些练习题，让学生 通过运用方式状语从句来 描述不同的行为方式。
3 小故事分享
讲述一个生动有趣的故事， 其中包含多个方式状语从 句，以激发学生学习的热 情。
条件状语从句
分岔路口
通过插图展示两条不同的道路， 引导学生理解条件状语从句的逻 辑关系。
学生收获
从学生的角度描述条件状语从句 的学习成果和应用场景。
实现目标
分享一个实例，说明条件状语从 句如何帮助我们设定和实现个人 目标。
目的状语从句
1
理论讲解
通过简洁明了的理论讲解，向学生介绍目的状语从句的特点。
2
实际应用
通过实际案例演示目的状语从句在不同场景中的运用。
3
练习与回顾
设计一些练习题，帮助学生加深对目的状语从句的理解。
状语从句(完整版)PPT课件
child, I often played in the park.”（当我还是个孩子的时候，我经常
在公园里玩。）
02
从句时态先于主句
有时从句的时态会先于主句，表示从句中的动作发生在主句动作之前，
如“After he finished his work, he went home.”（他完成工作后就
结果状语从句的谓语动作可以与主句 的谓语动作同时发生，也可以在其后 发生。
结果状语从句的谓语动作可以是已完 成的，也可以是未完成的。
结果状语从句的省略与倒装
01
当结果状语从句的主语与主句主 语一致，且从句谓语包含be动词 时，可以省略从句的主语和be动 词。
02
在某些情况下，为了强调或保持 句子平衡，结果状语从句可以采 用倒装语序。
作用
使句子表达更加完整、准确，增强语 言的逻辑性和连贯性。
状语从句的构成
01
02
03
引导词
引导状语从句的词有 when、where、because 、if、although等。
主语和谓语
从句中通常包含主语和谓 语，构成完整的句子结构 。
时态和语态
根据主句的时态和语态， 从句的时态和语态也会相 应变化。
倒装
有时为了强调或保持句子的平衡，可以将时间状语 从句中的部分成分倒装，如“Only when he arrived did we start the meeting.”（只有当他 到达时，我们才开始会议。）
03
地点状语从句
Chapter
表示地点的连词
01
where：在...地方
02
03
04
wherever：无论在哪里
倒装
英语语法讲解课件-状语从句 ppt课件
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状语从句分类
1. 2. 3. 4. 5. 6. 7. 8. 表示时间 表示地点 表示原因 表示结果 表示目的 表示条件 表示让步 表示比较
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表示时间
一、时间状语从句 • When, as ,while, • before, after, • till, Until, • as soon as, • The moment, the minute, the first time…. （名词性短语）
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E.G. 1. He was so angry that he left the room without a word. 他很生气,一句话不说就离开 了房间。 2. It is such a heavy box that nobody can move it. 3. The box is so heavy that nobody can move it. 4. The box is so heavy as nobody can move . 5. I didn’t go early, so that I didn’t get a seat.
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表示比较
八、比较状语从句
主要由 • than， • as...as, • the more…the more • 这类从句常常有一些成分没有表示出来:
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E.G.
• The more you eat, the fatter you are. • John is less clever than Tom. • He is not so/as clever as his brother.
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状语从句分类
1. 2. 3. 4. 5. 6. 7. 8. 表示时间 表示地点 表示原因 表示结果 表示目的 表示条件 表示让步 表示比较
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表示时间
一、时间状语从句 • When, as ,while, • before, after, • till, Until, • as soon as, • The moment, the minute, the first time…. （名词性短语）
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E.G. 1. He was so angry that he left the room without a word. 他很生气,一句话不说就离开 了房间。 2. It is such a heavy box that nobody can move it. 3. The box is so heavy that nobody can move it. 4. The box is so heavy as nobody can move . 5. I didn’t go early, so that I didn’t get a seat.
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表示比较
八、比较状语从句
主要由 • than， • as...as, • the more…the more • 这类从句常常有一些成分没有表示出来:
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E.G.
• The more you eat, the fatter you are. • John is less clever than Tom. • He is not so/as clever as his brother.
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状语从句-PPT课件
By the time he was fourteen, he had taught himself
advanced mathematics.
Each time he came, he would call on me.
You must show him in immediately he comes.
saw him.
--- Did you remember to give Mary the money you owed her? --- Yes, I gave it to her ______ I saw her.(’01全国春招）
A. while B. the moment C. suddenly D. once
2) She found her calculator _____ she lost it.(’00上 海）
3、原因状语从句：
通常由连词：because, as, since, now that引导。
注意： ① 在强调句中强调原因状语从句，只能用because引导， 不可用as或 since，如：
1) I do every single bit of housework____ my husband Bob just does the dishes now and then.(’04广西）
2) A. since B. while C. when D. as
2) He was about to tell me the secret____ some one patted him on the shoulder. (’02上海）
*when 可表示“如果”。如：
Don’t be afraid of asking for help_____ it is needed. (’03全国）
高中英语语法专题系列：状语从句课件(共78张)
till和 until跟主句里否定形式表示非延续性动作的谓语动词 连用表示“直到……才(开始)”，这时until和till 可用before 代替。Not 有时被no, nobody, nothing, never, hardly, little 等否定词所取代。 People do not know the value of their health till/until/ before they lose it. Don’t put off what you can do today until tomorrow . 今日事，今日毕。 = Never put off what you can do today until tomorrow.
5）unitl/till
till和 until引导时间状语从句时跟主句里肯定形式表示 延续性动作的谓语动词连用表示“到……为止”。 Walk until/ till you come to a white house. I will stay with her until/till he comes back.
before 常用句型 （必背句型） ①It will be + 时间段+before+ 一般现在时：要等多久才……. It will be five years before we meet again. ②It won't be long before+ 一般现在时：等不了多久就会…… It will not be long before you regret what you have done. ③It was +时间段+before +一般过去时：等了多久就…… It was minutes before the police arrived. ④It wasn't long before+ 一般过去时：没等多久就…… It was not long before I realized I was wrong.
状语从句ppt课件完整版
复杂。因此，在写作中要适度使用状语从句，保持句子的简洁明了。
拓展阅读资源推荐
语法书籍
《英语语法大全》、《英语语法 手册》等，这些书籍详细介绍了 英语语法的各个方面，包括状语
从句的用法和技巧。
在线资源
英语语法网、英语语法在线等网 站提供了丰富的英语语法知识和 练习题，可以帮助学习者更好地
掌握状语从句的用法。
02
用法说明
03
though和although在从句中不能与but连用，但可以与 副词still和yet连用。
04
as引导的让步状语从句需要部分倒装，即将表语、状语或 动词原形提到as前面。
05
even if和even though引导的从句表示强调的让步，意 为“即使，尽管”。
06
whether...or...和no matter+疑问词引导的从句表示“无 论...都...”，在句中位置灵活。
状语从句的结构和特点
状语从句通常由从属连词引导，从句中的谓语用非谓语形 式（不定式、分词、动名词等）。不同类型的状语从句有 不同的结构和特点，如时间状语从句常用when, while, as 等引导，条件状语从句常用if, unless等引导。
状语从句与并列句、复合句的关系
状语从句与并列句和复合句有密切关系。并列句由并列连 词连接两个或两个以上的简单句，而复合句则包含一个主 句和一个或多个从句。状语从句可以作为复合句中相反的假设条件，主句说明在这个假设条件下会出现的结果。常用if引导， 从句和主句的谓语动词都要用虚拟语气。
典型例句分析
Unless you change your mind, I won't be able to help you.（ 除非你改变主意，否则我帮不了 你。）
初中英语语法状语从句课件(共45张PPT)
八、让步状语从句
although/though
• 尽管互联网技术被广泛用于教学，但是传统教 学的作用是不可取代的。
• Although the Internet technology is widely used in classroom teaching, the role of traditional teaching cannot be replaced.
People’s lives have undergone dramatic change since mobiles were invented.
• 6. A句+until+B句/时间短语 ห้องสมุดไป่ตู้A句…直到B句…】
The little boy kept crying until he saw his mother. = The little boy did not smile until he saw his mother.
• 4. Before, after 1）Before+A句,B句=B句+before+A句/时间词
【在A句…之前，B句…】 2）After+A句，B句=B句+after+A句/时间词
【在A句..之后，B句…】
• 在广告发明之前，人们获得产品信息的方 式主要通过与其他人之间的交流。
• Before advertising was introduced, the major channel by which people get informed of product information had been to communicate with other consumers.
状语从句(完整版)--ppt课件
because, as, since, now that, for,和considering that, seeing that 这七个连词都用于表示表示原 因, 但在语气上一个比一个弱。
＊尽管／虽然／鉴于／如果／届时／
e.g. He walks when he might take a taxi. 虽然
The Queen will visit the town in May, when she will open the new hospital. 届时
How can you hope for mercy yourself when
4. 表示“随着…..”.常指一个行为是另一个行为的结果，
或一种状态随另一种状态变化。句中的动词多表示状态
的发展变化。As
she
grew
opplt课de件r,
she
became
more
beautiful. 5
while:持续性动词 ／进行时
＊一般或现在情况
e.g. I like listening to music while I am doing my homework.
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考点:名词短语引导时间状语从句
• 1. When every time I was in trouble, he would come to help me.
• 2. At next time you come, do remember bring your son here.
• 3. For the first time I met the girl. I felt in love with her.
We clean the classroom before we leave school every day. It will not be long before you regret for what you’ve done.
＊尽管／虽然／鉴于／如果／届时／
e.g. He walks when he might take a taxi. 虽然
The Queen will visit the town in May, when she will open the new hospital. 届时
How can you hope for mercy yourself when
4. 表示“随着…..”.常指一个行为是另一个行为的结果，
或一种状态随另一种状态变化。句中的动词多表示状态
的发展变化。As
she
grew
opplt课de件r,
she
became
more
beautiful. 5
while:持续性动词 ／进行时
＊一般或现在情况
e.g. I like listening to music while I am doing my homework.
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考点:名词短语引导时间状语从句
• 1. When every time I was in trouble, he would come to help me.
• 2. At next time you come, do remember bring your son here.
• 3. For the first time I met the girl. I felt in love with her.
We clean the classroom before we leave school every day. It will not be long before you regret for what you’ve done.
状语从句公开课 PPT课件
I was walking down the street while I heard someone calling for help. when
3. When 还以引导条件状语从句相 当于if
How can I explain it to you when / if you won’t listen.
4.Adverbial Clauses of Place
(地点状语从句）
5.Adverbial Clauses of Purpose (目的状语从句） 6.Adverbial Clauses of Result （结果状语从句）
7.Adverbial Clauses of Comparison（比较状语从句）
• __C____ it is possible to test this medicine on
• human patients.
• A. since
B. after C. before
D. when
• 3. (06四川)－Why didn’t you tell him about the
• meeting?
4. “趁……”
1. Before they got to the bus stop, the bus had gone. 在..之前
2. It will be 5 years before he returns to his motherland. 多久之后才…
3. We waited a long time before he came out.
（ 让步）
• As he wasn’t ready in time, we went without him. （原因）
• Do as I told you. / do as you like. （ 方式 ）
3. When 还以引导条件状语从句相 当于if
How can I explain it to you when / if you won’t listen.
4.Adverbial Clauses of Place
(地点状语从句）
5.Adverbial Clauses of Purpose (目的状语从句） 6.Adverbial Clauses of Result （结果状语从句）
7.Adverbial Clauses of Comparison（比较状语从句）
• __C____ it is possible to test this medicine on
• human patients.
• A. since
B. after C. before
D. when
• 3. (06四川)－Why didn’t you tell him about the
• meeting?
4. “趁……”
1. Before they got to the bus stop, the bus had gone. 在..之前
2. It will be 5 years before he returns to his motherland. 多久之后才…
3. We waited a long time before he came out.
（ 让步）
• As he wasn’t ready in time, we went without him. （原因）
• Do as I told you. / do as you like. （ 方式 ）
状语从句(23张PPT)初中英语专项复习课件
时间状语从句的引导词
when while as
when, while, as：当…时
①既可以加持续性动词也可以加终止性动词 ②从句动作与主句动作可同时发生也可先后发生
When he arrived all the guests had left. Mary was having dinner when I saw her.
让步状语从句
though和although的用法 （1） 两词用法基本相同，although更加正式一些 （2） even though结构中的though不可以换为although （3） 两词不可与but连用，但是可以和yet, still连用
Though/although she works very hard, she makes slow progress. Though/although she is young, she has travelled to many countries.
条件状语从句
If the weather is terrible next week, we will put off the meeting. As long as you promise to come, I will wait for you. You will be late unless you hurry up. In case it rains, do not expect me.
3. such + 形容词+不可数名词+ that…
This was such fine music that it was worth listening to it again.
比较状语从句
1.在复合句中起比较状语作用的从句称为比较状语从句
状语从句(29张PPT)初中英语专项复习课件
状语从句
初中英语专项复习
状语从句是指句子的状语由一个从句充当， 用来 修饰主句中的动词、形容词或副词等。状语从句由从 属连词引导， 与主句连接， 放在句末时， 一般不在 前面加逗号。状语从句根据它表达的意思可分为时间 、原因、条件、比较、结果、目的等类型。
一、状语从句的种类
状语从句 的种类
引导词
)
color looks terrible.
He ran as fast as he
as＋原级＋ as… could to the top of
比较状语 比较级＋than＋ the hill.
从句 比较对象
John swims better
than Jim does.
状语从句 的种类
引导词
例句
He spoke so fast that
5. when, while, as意为“当……的时候”。 (1)when表示在某一特定的时间点(段)，主句的动作和
从句的动作同时发生或先后发生。when引导的时间 状语从句的谓语动词既可以是非延续性动词，也可 以是延续性动词。如： When we lived in town, we often went to the theatre. 我们住在城镇里的时候常去剧院看戏。
last night. 昨晚直到12点我回来他才停止工作。
7. as soon as… 意为“一……就……”， 强调主句的动 作紧接着从句的动作。如：
As soon as I arrive in Beijing, I will call you. 我一到达北京就会打电话给你。 8. so… that, such… that意为“如此……以至于……”， 引导结果状语从句。基本规则是：so后面接形容词 或副词， such后接名词。但有几点要特别注意： (1)such是形容词， 它所修饰的名词可以是可数名词， 也可以是不可数名词；名词前面可以带形容词， 也 可以不带。如果其后是单数可数名词， 前面需加不 定冠词a或an。因此， such… that… 的句型结构可 分为以下三种：
初中英语专项复习
状语从句是指句子的状语由一个从句充当， 用来 修饰主句中的动词、形容词或副词等。状语从句由从 属连词引导， 与主句连接， 放在句末时， 一般不在 前面加逗号。状语从句根据它表达的意思可分为时间 、原因、条件、比较、结果、目的等类型。
一、状语从句的种类
状语从句 的种类
引导词
)
color looks terrible.
He ran as fast as he
as＋原级＋ as… could to the top of
比较状语 比较级＋than＋ the hill.
从句 比较对象
John swims better
than Jim does.
状语从句 的种类
引导词
例句
He spoke so fast that
5. when, while, as意为“当……的时候”。 (1)when表示在某一特定的时间点(段)，主句的动作和
从句的动作同时发生或先后发生。when引导的时间 状语从句的谓语动词既可以是非延续性动词，也可 以是延续性动词。如： When we lived in town, we often went to the theatre. 我们住在城镇里的时候常去剧院看戏。
last night. 昨晚直到12点我回来他才停止工作。
7. as soon as… 意为“一……就……”， 强调主句的动 作紧接着从句的动作。如：
As soon as I arrive in Beijing, I will call you. 我一到达北京就会打电话给你。 8. so… that, such… that意为“如此……以至于……”， 引导结果状语从句。基本规则是：so后面接形容词 或副词， such后接名词。但有几点要特别注意： (1)such是形容词， 它所修饰的名词可以是可数名词， 也可以是不可数名词；名词前面可以带形容词， 也 可以不带。如果其后是单数可数名词， 前面需加不 定冠词a或an。因此， such… that… 的句型结构可 分为以下三种：
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6.next time, the first time, the last time, every time 等
Eg: 1). 下次你进城一定来看我们。 Be sure to call on us next time you come to town. 2). 我第一次见他时，他给我留下了好印象 He left me a good impression the first time I met him. 3). 我每次见到他，他都是一付痛苦的表情 Every time I see him he looks miserable. 4).上一次我见到他时，他看上去很开心。
③当not until位于句首时，主句 中的主谓要使 用倒装语序。 Eg: 1)直到那时，我才知道我错了。 I didn’t know I was wrong until then. = Not until then did I know I was wrong. 2) Tom didn’t leave until she came back. = Not until did Tom leave she came back. 3) 直到我开始工作，我才认识到了我已蹉跎了 几多岁月。 Not until I began to work did I realize how much time I had wasted .
Adverbial Clause
状语从句
九种常用的状语从句
1.时间状语从句 3.原因状语从句 5.让步状语从句 7.目的状语从句 9.比较状语从句 2.地点状语从句 4.条件状语从句 6.结果状语从句 8.方式状语从句
状语从句的定义、功能、分类
定义：在复合句中作状语的从句 功能：状语从句在主从复合句中修饰主句中 的动词，形容词或副词，或整个主句 分类：按意义可分为时间、地点、原因、目 的、结果、条件、方式、比较、让步等状语从 句。 位置：从句的位置放在句首，也可放在句末。 放在句首时，从句后面常用一个逗号，放在句 末时，从句前一般不用逗号。
考 点 难 点
1、各种从属连词的含义及用法 比较； 2、no matter wh- 与 wh-ever 引 导的从句的区别； 3、状语从句的时态问题；
4、状语从句倒装及省略；
5、状语从句与其它从句的区别。
一.时间状语从句
引导时间状语从句的从属连词 1.基本类：
when , while , as , before , after , since , till , until , once, as soon as, etc. 2. 名词类 the moment ,the minute, the second, the instant(一…就); every time, each time, the last time, the first time, the day, the year, the morning etc.
③表示 一边……一边……，强调从句和主句中两 个动作交替进行或同步进行。 Eg:1). 他一边走，一边不时地往后看。 He looked behind from time to time as he went. 2). 她一边洗澡，一边唱歌 She is singing a song as she took a bath. 3) 他在街上一边走，一边高兴地唱着歌。 As he walked along the street, he sang happily.
3. 副词类：
immediately, directly, instantly, etc. (一...就...) 4.句型类： no sooner…than…, hardly/scarcely… when…, etc. (一… 就…)
注意： 1. when, as, while 的区别
when ①when表示“当、、、的时候”从句中谓动既可用 瞬间性动词；又可用连续性动词。 Eg: 1).当他看见她的时候，就挥手打了个招呼。 He waved a hello when he saw her. （when表示时间点） 2).当他们还在说笑的时候，老师进来了。 When they were still talking and laughing, the teacher came in. （when表示段时间）
② Not……until/till表示直到……才 ，主句用瞬间性
动词。 Eg: 1: I didn't leave until / till she came back. 2. People do not know the value of their health till/ until they lose it.
3. before： ① 含义 1． We had sailed four days and four nights before we saw land. ―……才” 2． We hadn’t run a mile before he felt tired.“不到…就” 3． Please write it down before you forget it. ―趁……‖ 4．Before I could say a word, he had gone away.
④ as: 定语从句；比较状语从句；原因状语从句； 方式状从句, 让步状语从句
2. till, until和not…until
①until /till用于肯定句时，表示直到 … 为止，主句必
须为连续性动词。 Eg: 1. We shall wait until / till he comes back. 2. Everything went well until /till that accident happened.
The last time I spoke to Bob, he seemed very happy.
7.by the time by the time 也可以引导时间状语从句，意为 到…… 时为止，主句一般要用完成时态。
Eg: 1). By the time he was fourteen, Einstein had learned advanced mathematics all by himself. 爱因斯坦到十四岁时就自学完了高等数学。 (从句为一般过去时，主句要用过去完成时) 2). 在你回来之前我将会做完我的活儿。 I shall have finished my work by the time you return. (从句为一般现在时，主句要用将来完成时)
―还没来得及”
② 句型It will be/was＋一段时间＋before…―还要过多 久才……‖ 如：还有2年他才离国。 It will be two years before he leaves the country. ③ 句型It will be/was not＋一段时间＋before…―没过 多久就……‖。 如：没过2年他就离国了 It wasn’t two years before he left the country.
① as表示“当、、、的时候”，从句用瞬间性动 词 Eg: As she left the room she remembered that book. As I stopped my car , a man came up to me. ② as表示随着时间推移 Eg: 随着时间的推移，天气变得越来越暖了。 As time goes on, it's getting warmer and warmer. As the sun rose the fog dispersed. As he grew older, he began to go deaf.
②. 当从句动作发生于主句之前， 只能用when，while和 as则表示同 时发生
• Eg: When you have finished you work, you may have a rest.
wh。
Eg: Strike while the iron is hot. 趁热打铁。 Lucy listened carefully while Tom read the letter. ②while有时可以作并列连词，表示对比，可译成 而……。 Eg: 1). 我喜欢英语而他却喜欢数学。 I am fond of English while he likes maths. 我们睡觉而老师上课。 2). We slept while the teacher had classes.
② 句型It is/has been＋一段时间＋since… Eg: 1). It’s two years since he was a college student. 他大学毕业已有两年了 2). It has been just a week since we arrived here. 我们 到那里有一个星期了。 ever since 从那时起直至现在，此后一直。 Eg: He has been sad ever since the death of his wife.
②on/ upon doing Eg: On arriving home he called me up.
③ hardly / scarcely……when
, no
sooner…… than 主句通常用过去完成时，从句用一般过去时。
Eg; 他刚出发就想起家来。 He had no sooner started out than he felt homesick. 注意： 当hardly, scarcely, no sooner位于句子的开头时， 主句须用倒装语序。 Eg: No sooner had he started out than he felt homesick. Hardly /Scarely had I got home when it began to rain.