介词、连词

　　一. 介词

　　1. 介词概述：介词表示它与后面的名词或代词与其他句子成分的关系。介词是虚词，不能单独做句子成分。介词在英语中用法很活，也无一定规律可循。在初中范围内还应学一个记住一个，特别是那些和动词的特殊搭配。

　　2. 常用介词的意义和用法。

　　⑴ 时间或地点介词in、on、at的用法区别：

　　表示时间时, in表示在一段时间里(在将来时句子中则表示在一段时间之后), on表示在具体的某一天或者某天的上下午等, at表示在某个时刻或者瞬间;

　　表示地点时, in表示在某个范围之内, on表示在某个平面上或与一个面相接触,at则表示在某个具体的场所或地点。如：

　　He was born on the night of May 10th.

　　I usually get up at 7：00 in the morning.

　　His glasses are on the desk.

　　My brother is at the bus stop.

　　⑵ after与in表示时间的用法区别：“after+(具体时刻/从句)”表示“在…时刻之后”常用于一般过去时态;“in+(一段时间)”表示“在(多久)之后”,常用于将来时态。如：

　　He said that he would come back after 6：00.

　　My father is coming back from Astralia in about a month.

　　⑶ since与for表示时间的用法区别：“since+(具体时刻/that-从句)”表示“自从…起一直到现在”,“for +(一段时间)”表示“持续一段时间”,都常用于完成时态;如：

　　My father has worked in this factory since 1970.

　　My father has worked in this factory for over 30 years.

　　⑷ by、in与with表示方式的用法区别：都可以表示“工具、手段”,但是by主要表示“乘坐”某个交通工具或“以……方式”,在被动句中可以表示动作的执行者;in表示“使用”某种语言/文字,with表示“使用”某个具体的工具、手段。如：

　　We write with our hands and walk with our feet.

　　Please speak in English.

　　Let’s go to the zoo by bus.

　　It was invented by Adison.

　　⑸ about与on的用法区别：都可以表示“有关…”,但是about的意义比较广,而on主要表示“有关…(专题/课程)”。如：

　　Tom is going to give a speech on the history of China.

　　They are talking about the English test.

　　⑹ through与across、over的用法区别： through指“穿过…(门洞/人群/树林)”; across和over可以指“跨越…(街道/河流)”,可互换,但是表示“翻过…”时只能用over. 如：

　　Just then a kangaroo (鼠)ran across the road.(就在那时一只袋鼠跑过路面)

　　There is a bridge across/over the river.(河上有座桥)

　　They climbed over the mountain and arrived there (他们翻过大山到达了那里)/

　　The visitors went through a big gate into another park.(参观者们穿过一个大门来到另一个公园)

　　(7)as与like的区别：两个词都表示“像……”,但是as译为“作为……”,表示的是职业、职务、作用等事实,而like译为“像……一样”,表示外表,不是事实。如：

　　Let me speak to you as a teacher.(我以老师的身份和你讲话。)

　　Let me speak to you like a teacher.(让我像一位老师一样和你讲话)

　　(8)in front of 与in the front of：in front of“在…的前面”, 与in the front of“在…的前部”。如：

　　A group of people was standing in front of the hall.

　　In the front of the hall stood a group of people.

　　(12)except与besides的区别：except“除了”,表示排除掉某人物,即不包含;而besides“除了”则表示包含,即“不仅……又……”。如：

　　Everyone went to the park except Tom.(除了Tom,大家都去了公园)(Tom没有去公园)/

　　Besides maths he also studied many other subjects.(除了数学之外,他还学其他许多功课)(“数学”也是他学的功课之一)

　　连词

　　1.连词概述：连词是一种虚词，用于连接单词，短语或句子，但不单独做句子成分。按照连词的性质，可将连词分为并列连词和从属连词。并列连词如：and，but，or，for等，它们即可连接单词，短语，又可连接句子。从属连词如：when，before ，because等，它们主要引导名词性从句。

　　2.常见连词的用法：

　　1)并列连词 的用法： 并列连词有：and, but, or, nor, so, for yet, however, as well as, both...and, not only...but also, either...or, neither...nor, still,

　　And： 连接单词短语句子 。如：Tom and I study in the same school.

　　But, or ：I have a pen but no pencil. / Would you like coffee or tea?

　　Nothing but除了，只有： I did nothing but watch it.

　　Or表示否则：如： Hurry up or you will miss the train.

　　for 表示后面的句子是原因。如： He is good at piano for he practices harder than others.

　　Not only…but also 不仅…而且。可并列主、谓、宾、表及句子。主语并列时，谓语要就近一致。如: Not only he but also I am a nurse.

　　As well as 以及，同样。并列单词、短语、句子。并列主语时，动词要随前面的主语变化 .如：He works as well as he can

　　Either…or 既…又…，或…或…，并列主、谓、宾、表及状语 ，如：Either come in or go out.

　　Neither…nor 既不…也不， 并列主、谓、宾、表、状语，并列主语时，谓语就近一致。如：Neither you nor he is lazy.

　　Both…and 和，既…也，并列主、谓、宾及表语。I can speak both English and French.

　　nor 也不，引导句子要倒装 。如：He can not play the piano, nor can I.

　　so 因此，所以，不和because连用。如：You like swimming, so do I.

　　1) 从属连词的用法： 从属连词有：after, when, before, as, while, since, until, till, if, unless, because, than, that, whether, so that

　　after 表示“时间”，在…之后。如：After I finished the school, I became a worker in the factory.

　　Although/though 表示让步， “尽管”。如： Although she is young, she knows a lot.

　　as 表示时间，“当…时”，方式“象…”，原因，“由于、因为”让步，“尽管、虽然” 。如： As it was rainy, we couldn’t go out now.

　　As if/as though 表方式，“似乎、好像” 。如： He told us such a story as though he had been there before.

　　As long as/so long as 表条件，“只要” 。如： As long as I am here, I’ll go to help you.

　　As soon as 表时间，“一…就…”。如： I will call you as soon as I come back.

　　because 表原因，“因为”。如： I have to practice more because I am not good at English.

　　before 表时间，“在…之前’’ 。如： You should think more before you do it.

　　Even if/ even though 表让步，“即使”。如： You should try again even if you failed.

　　Hardly…when 表时间，“(刚)一…就”。如： Hardly I entered the gate when the bell rang.

　　if “假如”，引导条件状语从句。如： We will stay at home if the rain doesn’t stop.

　　“是否”，引导宾语从句。如; I don’t know if he goes shopping.

　　In order that 表目的，“为了，以便”。如： We study hard in order that we can pass the exam.

　　No matter +疑问词 表让步，“无论，不管”。如： No matter what you do, you should try your best.

　　No sooner…than 表时间，“刚一…就…”。如： No sooner had I come home than it began to rain.

　　once 表时间，“一旦…”。如： Once you read this book, you’ll never forget it.

　　since 表时间，“自从…以来”.如： He has been in this city since he left school.

　　表原因，“既然，由于” 。如: Since the job is dangerous, let’s do it more carefully.

　　so far as/as far as 表条件，“就…而言，就…而论”.如：As far as I know, it is easy for you to speak in English.

　　So that 表目的，“以便” 。如： Speak loud so that everybody can hear clearly.

　　So…that 表结果“如此,以致”。如： He got up so early that he caught the early bus.

　　than 表示比较，“比” 。如： Things were worse than we thought.

　　unless 表条件，“除非，如果不” 。如： You will fail in the test unless you study hard.

　　Until/till 表时间，“直到…为止” 。如： I’ll wait till my mother comes back.

　　when 表时间，“当…时’’。如： When they got there, the train has left.

　　whether “是否”引导名词性从句 。如： Whether he can come to see us is unknown.

　　表让步，“不管/无论、是否”。如：Whether she is rich or poor, she is always happy.

　　while 表时间，“当…时” 。如： While he was in Beijing, he visited the Great Wall.

　　whenever 表时间，“无论什么时候”。如： Whenever you meet any trouble, tell me at once.