1.简单句、并列句和复合句
① 句子种类两种分类法
按照句子的用途，英语的句子可分：陈述句(肯定、否定)、疑问句(一般、特殊、选择、反意)、祈使句、感叹句等四种。
按照句子的结构可分：简单句并列句和复合句三种。
简单句只有一个主语或并列主语和一个谓语或并列谓语。并列句由并列连词and, but, or，so等)或分号(;)把两个或两个以上的简单句连在一起构成。复合句：含有一个或一个以上从句的句子。复合句包含：状语从句\名词性从句(主语从句、宾语从句、表语从句和同位语从句)和定语从句等三种。
② 并列句的分类
并列句指把两个同等重要的句子连接在一起，句子之间常用and, not only…but also…, neither…nor…, then等并列连词连接。
表示选择关系常用的连词有：or, either…or…, otherwise等
表示转折关系常用的连词有：but, still, however, yet, while, when等。
表示因果关系常用的连词有：so, for, therefore等。
2.状语从句：
(1)状语从句的分类
状语从句通常修饰主句的动词或整个句子，由从属连词引导，从属连词在从句中不充当句子成分。根据状语从句所表达的不同意义和功能，可分为时间、地点、原因、条件、目的、结果、让步、比较、方式等状语从句。
(2)连接状语从句的词语
时间状语从句：when, whenever每当……，after, before, as, as soon as, hardly/ scarcely...when..., no sooner...than.。.一……就……，while, till, until, since, once。名词词组the first time第一次，last time最后一次，every/each time每次，the next time下次，the next day第二天， the moment, the minute, the second, the instant 一……就……;副词immediately, instantly, directly等也可作连词使用。
原因状语从句：because, since, as, now that。
地点状语从句：where，wherever(无论那里)。
让步状语从句： no matter who/whom/what/which/how/when/where, though, although, as, even if /even though, whatever, whoever, however, wherever, whenever等。
条件状语从句： if, unless, as/so long as(如果;只要)，in case (万一); on condition that(如果)， suppose, supposing, providing, provide。
目的状语从句：in order that (为了)，so that (以便)。
比较状语从句：(not) as/so…as…，than…, the more…the more…(越……越……) 引导。
方式状语从句：as(正如;按照)，as if/as though (好像)引导。
结果状语从句： so that (结果是)， so/such…that (如此……以至于)。
(3)从句中的语序
复合句中通常采用陈述语序。但是，在下面的几种情况下，状语从句多采用倒装语序：
①当连词as, though连接让步状语从句时，作表语的名词、形容词、动词通常置于句首，构成部分倒装语序。例如：
Much as I have traveled, I have never seen anyone who’s as capable as John。
Try as she might, Carol couldn't get the door open。
Strange though it may seem, I like housework。
②在so/such...that.。.结果状语从句中，so+形容词/副词或such+名词置于句首时，主句采用部分倒装语序。例如：
So successful was her business that Marie was able to set up new branches elsewhere.
Such was the force of the explosion that windows were blown out。
③在hardly/scarcely...when..., no sooner...than.。.句式中，把hardly/scarcely/no sooner置于句首时，第一个分句采用部分倒装语序，即把第二个分句用陈述语序。例如：
Scarcely had he sat down when there was a knock at the door。
④ however与形容词、副词一起引导让步状语从句，句子采用陈述语序。例如：
However amusing the story is, I have to put it away and focus my attention on study this week。
⑤ 在the +比较级the+比较级句式中，只是把形容词或副词置于句首，句子仍然采用陈述语序。例如：Education is about learning and the more you learn, the more equipped for life you are。
(4)从句和主句中谓语动词的时态
在复合句中，主句和从句的谓语动词时态一般遵循以下的规律：
①表示“同时”意义的连词as, when, as soon as, the moment, while 等连接的时间状语从句，主句和从句时态基本一致。例如：As time passed, things seemed to get worse。
② 表示“将来”意义的条件、时间和让步状语从句中多用一般现在时，而主句用一般将来时，被称为“主将从现”。例如：Tom won’t go to sleep unless his mother tells him a story。
Once I get him a job, he’ll be fine。
③ since引导的时间状语从句多用一般过去时，而含有since从句的主句通常用现在完成时。例如：I haven’t met her since I left university。
④在句式hardly/scarcely…when…, no sooner…than…中，第一个分句中过去完成时，第二个分句用一般过去时。例如：She had hardly sat down when the phone rang。
⑤ 在as if/though 引导的状语从句中，如果表示一种与事实相反夸张，从句多用一般过去时或过去完成时。例如：She stared at me as though I were a complete stranger。
(5)状语从句的省略
当从句的主语与主句的主语相同时，被动结构的状语从句，可省略与主句相同的主语和助动词，保留连词+过去分词;主动结构的状语从句，可省略与主句相同的主语和助动词，保留连词+现在分词。例如：We all know that, if not carefully dealt with, the situation will get worse。
Though lacking money, his parents managed to send him to university。
(6)状语从句被用于强调结构中
状语从句作为被强调部分用于强调结构时，一律用It is/was …that…，不能用when代替that。句子用陈述语序。注意：当强调Not until +时间/时间状语时，主句的谓语动词不再采用倒装语序。例如：It was not until the war was over that the soldier was able to return home。
3.名词性从句
(1)名词性从句分类：
按照在句中的功能，名词性从句分为：主语从句、宾语从句、表语从句和同位语从句四种。
(2) 名词性从句的连接词
名词性从句的连接词可分为三类：that无词义，在从句中不担任成分，有时可被省略;表示“是否”用whether，只有在宾语从句中，whether可被人if代替。Whether和if在从句中不担任成分。如果从句缺少主语、表语、宾语、或定语等句子成分，用连接代词what, whatever, who, whoever, whom, whose, which;如果从句缺少状语，用连接副词when, where, how, why。
由于连接代词与连接副词在句中不再是疑问句，因而从句中谓语不用疑问语序。连接代词与连接副词在从句充当句子成分，而连接词whether 和if(是否)，在从句中不充当句子成分，只起连接作用。
(3) 名词性从句中的特殊时态
① 在以下三种主语从句中，主语从句的谓语动词要用“should+动词原形”， should可省略。
(1)It is+形容词+that…句型。常见的形容词有important, necessary, natural, funny, strange, surprising, astonishing(令人惊讶的)等。
(2) It is +名词+that…句型。常见的名词有pity, shame, advice, suggestion, proposal(提议，建议)， requirement, request, desire, order等。
(3) It is+动词的过去分词+ that…句型。常见的动词有advise, order, propose, request, suggest, demand, require等。
②在insist(坚持)， urge (催促)， order(命令)， command(命令)， suggest(建议)，advise(建议)，recommend(建议，推荐)， request(请求，要求)， demand(要求)，require(要求，需要)等动词后的宾语从句中，谓语动词用“should+动词原形”， should可省略。
③ 在含有advice, order, demand, proposal(提议)， requirement, suggestion等名词的表语从句、同位语从句中，谓语动词用“should+动词原形”，should可省略。
④在一些表示惊讶、意志等感情色彩的名词性从句中，谓语动词用“should+动词原形”或“should +have done”，译为“竟然，居然”。例如：
I am surprised /shocked that you should speak in such a way。
I find it astonishing that he should be so rude to his mum。
It is strange /surprising that she should not have been invited。
I am glad that your story should have won the first prize。
4. 定语从句
(1)定语从句的分类
定语从句分为限制性定语从句非限制性定语从句两种。限制性定语从句对先行词起修饰和限制作用，而非限制性定语从句对先行词起补充和解释说明作用。通常限制性定语从句与先行词之间没有逗号，而非限制性定语从句与先行词之间有逗号隔开。
(2)定语从句的关系代词和关系副词
定语从句一般由关系代词和关系副词引导。关系代词有：who, whom, whose, which, that, as;关系副词有：when, where, why。关系代词和关系副词必须位于从句之首，主句的先行词之后，起着连接先行词和从句的作用，同时在从句中又充当句子成分。
(3)关系代词和关系副词的用法：
①当先行词为人时用who 作主语，whom作宾语;
②当先行词为物或整个句子时用which，可作主语或宾语;
③先行词为人、物时用that ，可作主语或宾语;
④ whose用作定语，可指人或物;
⑤ 关系副词when指时间，在定语从句中作时间状语;
⑥where(指地点，在定语从句中作地点状语);why指原因，在定语从句中作原因状语。
(4)限制性定语从句与非限制性定语从句的区别
①限制性定语从句：从句与主句关系密切，去掉从句，主句意义不完整，甚至不合逻辑。例如：I was the only person in our office who was invited。(去掉定语从句，句意就不完整)
② 非限制性定语从句：从句与先行词关系不密切，去掉定从句，意思仍然完整。形式上用逗号隔开，不能that用引导。例如：His movie won several awards at the film festival, which was beyond his wildest dream. (去掉定语从句，主句的意思仍完整)
(5)使用定语从句时需注意的几个问题
①用that而不用 which的情况：先行词为不定代词all, anything, nothing, much…;先行词有最高级修饰，有序数词修饰;先行词有only, very, any等词修饰;先行词既有人又有物时。例如：There is nothing that can prevent him from doing it。
The first place that they visited in Guilin was Lijing。
This is the best coffee maker that I have ever been made。
Mr Smith is the only foreigner teacher that he knows。
② 用which而不用 that的情况：引导非限制性定语从句;指代整个主句的意思;用于介词 的后面+ 关系代词。例如：Chan’s restaurant on Baker Street, which used to be poorly run, is now a successful business. For many cities in the world, there is no room to spread our further, of which New York is an example。
③ 关系代词as的用法
a. 当现行词为 the same +名词，such+名词时，要用关系代词as引导定语从句。例如：
I want to buy the same shirt as yours。
Such machines as are used in our workshop are made in Germany。
b. as可指代主句的内容，引导的非限制性定语从句既可放在主句之前，也可放在主句之后。常用于下列句型：as is known to all, as is said, as is reported, as is announced, as we all know, as I expect 等。例如： He got the first place again in this mid-term examination, as we expected。
c. as 引导非限制性定语从句时与which的区别
当主句和从句语义一致时，用as引导;反之，用which来引导非限制性定语从句;当非限制定语从句为否定意义时，常用which引导。例如：
He made a long speech, as we expected。
He made a long speech, which was unexpected。
④关系代词在从句中作主语时，从句的谓语动词单数还是用复数应由先行词决定。例如：
The man who lives downstairs makes it a rule to run in the park in the morning。
⑤ 引导定语从句的关系副词有时可以用“介词 + which”来代替。例如：
October 1, 1949 was the day on which (= when) the new China was founded。
⑥在”介词+关系代词”结构中，关系代词只能用which和whom，且不能省略;如果介词在句末，关系代词可用which, that, whom, 口语中也可用who，且可省略。例如：
The man (whom/ who/ that) you were talking about is proves to be friendly。
四、注意事项
1.状语从句与其它相似结构的辨析
① It is/was+被强调的时间状语+ that+其它句子成分，其特点是去掉It is/was和that原句仍然成立。例如：It was at midnight that we got home。
② It is/was+时间+when/before+从句 表示“当……发生时，时间是……”。例如：
It was late evening when the doctor arrived。
③ It will be/was+时间段+before+句子，表示“要过……才会发生某事”或“过了……发生了某事”。例如：It will be years before we find a cure for cancer。
④ It is/has been + since +句子， 表示“自从……以来，时间过了……”。例如：
It’s three years since I last saw her。
2. 分隔定语从句
有时，定语从句不紧跟先行词之后，中间被一个插入语、状语、定语或谓语隔开。例如：
There is an expression in his eyes that I can’t understand。
For these football fans, it was an exciting moment this year, when for the first time in years their team won the world cup。
Do you remember one afternoon ten years ago when I came to your house to borrow a necklace?
The film brought the hours back to me when I was taken good care of in that faraway village。
Let’s go into the restaurant across the street where you can sit down。
3.定语从句与同位语从句的区别
在定语从句中，关系代词或关系副词作某种句子成分，定语从句对先行词起修饰和限制作用，而在同位语从句中，从对前面的抽象名词起补充和解释作用，连接词不在从句中充当句子成分。例如：
We heard the news that our school team had won the game. (同位语从句， that在从句中不作句子成分)
The news that he told me yesterday proves true. (定语从句， that 在从句中作told的宾语)
The possibilities that she was offered seemed very great. (定语从句， that 在从句中作offered的宾语)
She is worried about the possibility that she might lose her job。( 同位语从句， that在从句中不作句子成分)
4. 定语从句与名词性从句的辨析
①与主语从句的辨析
As is known to all, the natural resources are reducing day by day. (非限制性定语从句)
It is known to all that the natural resources are reducing day by day. (主语从句)
What is known to all is that the natural resources are reducing day by day. (主语从句)
|
|
