初中英語知識點總結(jié)：初中英語語法——連詞用法精講

　　連詞可以分為并列和從屬連詞兩類，下面就兩類連詞分別加以講解。

　　漫談一：并列連詞

　　并列連詞根據(jù)它的意義和用途，可分為并列、轉(zhuǎn)折、因果和選擇四種。

　　一、表示并列關(guān)系的連詞有：and, both…and…, not only… but also…和neither…nor…等

　　1、and：和，并且

　　A：基本用法：

　　“and”表示 “和”、“并且”的意思，用來連接對等關(guān)系的字和字，片語和片語，句子和句子。

　　I enjoy basketball , football and table tennis.

　　The weather becomes colder and colder.

　　B:特別用法：

　　祁使句后連接and，有條件句作用，此時and=if you…,you’ll…

　　Go straight on, and you’ll see the library.==If you go straight on, you will see the library.

　　2、both…and…既…也…,(兩者)都…

　　A、both…and…構(gòu)成的詞組作主語時,謂語動詞用復(fù)數(shù)。

　　Both Jim and Kate are from England.

　　B、both…and…否定句表示部分否定。

　　You can’t speak both German and English.

　　Both my father and my mother aren’t doctors.

　　3、neither…nor…:既不…也不…

　　neither…nor…連接兩個并列主語時,謂語動詞靠近哪個主語就與哪個主語保持 “人稱”和 “數(shù)”的一致，即采取就近原則。

　　Neither I nor he has seen the play before.

　　4、not only…but also…:不但…而且…

　　not only…but also…連接兩個主語后的謂語動詞也遵循就近原則。

　　Not only the mother but also the children are ill.

　　二、表示轉(zhuǎn)折關(guān)系的連詞有：but, however, yet, still，while等。

　　Mary was a nice girl, but she had one shortcoming.

　　Tom got up early, yet he failed to catch the train.

　　He was very tired, still he kept on walking.

　　Your composition is fairly good, however, there is still some

　　room for improvement.

　　Jane is hard working ,while her sister is quite lazy.

　　三、表示選擇關(guān)系的并列連詞有：or, either…or…,whether… or…等。

　　1、or：或、否則

　　A:基本用法

　　or 表示 “或” 的意思，使用于兩者之中選擇一個的時候。

　　----Is your friend English or American? ----American.

　　He doesn’t like dumplings or noodles.

　　B:特別用法

　　祁使句后連接or ，表 “如果…,否則…”,有轉(zhuǎn)折的意思，此時 or =if you don’t …,you’ll …

　　Hurry up, or you’ll be late.=If you don’t hurry up, you’ll be late.

　　2、either…or…:或者…或者…; 不是…就是…;要么…要么…

　　A.either…or…連接兩個并列主語時,謂語動詞靠近哪個主語就與哪個主語保持 “人稱”和 “數(shù)”的一致，即就近原則。

　　Either you or I am right.

　　Does either she or they like English?

　　B.由either…or…引導(dǎo)的否定句是完全否定。

　　She isn’t either a student or a teacher.

　　3、whether…or…不管…還是…

　　She is always cheerful, whether at home or at school.

　　四、表示因果關(guān)系的并列連詞有：for(因為)，so(所以)。

　　He is not at school today, for he has a bad cold.

　　It was late, so I went home.

　　漫談二：從屬連詞

　　從屬連詞是用來連接各種狀語從句和名詞性從句的。

　　一、引導(dǎo)時間狀語從句的從屬連詞有：before, after, when, while, as, till, until, since, as soon as等。

　　After they had planted their crops, they took a rest.

　　We have learned six lessons since he began to teach us.

　　As soon as he gets to Beijing, he’ll call me.

　　1、when, while, as 都表示“當(dāng)……時”，when從句謂語動詞既可以是瞬間動詞也可以是延續(xù)性動詞，可用于主從句動作同時發(fā)生或從句動作先于主句動作發(fā)生。while從句謂語動詞只能是延續(xù)性動詞，側(cè)重主從句動作同時發(fā)生。as引導(dǎo)一個持續(xù)性動作，多用于主從句動作同時發(fā)生，強調(diào)“一邊……一邊”。

　　When I came in, my father was cooking.

　　I came in when/while my father was cooking.

　　He sang as he walked.

　　2、until用法：當(dāng)主句謂語動詞是延續(xù)性動詞時，主從句都用肯定式，譯為“直到……為止”;當(dāng)主句謂語動詞是瞬間動詞時，主句用否定式，從句用肯定式，即not…..until, 譯為“直到……才”。

　　Mr. Green waited until his children came back.(格林先生一直等到他的孩子們回來)

　　Mr. Green didn’t go to bed until his children came back. (格林先生直到他的孩子們回來才睡覺)

　　二、引導(dǎo)條件狀語從句的從屬連詞有：if(如果), unless(除非，如果……不)等。

　　If you don’t go soon, you’ll be late.=Unless you go soon, you’ll be late.

　　三、引導(dǎo)原因狀語從句的從屬連詞有 because, as, since等。

　　because“因為”語氣最強,回答why提問時只能用because，其引導(dǎo)的從句可放在句首或句末;as“由于”、since“既然”語氣不如because強，引導(dǎo)的從句常置于句首;for是并列連詞，語氣最弱，對前面分句加以解釋或補充說明，其引導(dǎo)的分句常置于句末且用逗號隔開。

　　He didn’t go to school because he was ill.

　　As it was raining, we went there by bus.

　　Since everybody is here, let’s begin.

　　It must have rained last night, for the ground is wet.

　　注意： because與 so不能同時使用。

　　四、引導(dǎo)讓步狀語從句的從屬連詞有：although/though(雖然，盡管), even though/if (即使)

　　Although/ Though it is a very young country, it is very rich.

　　Even if/ though you were here yesterday, you couldn’t help him.

　　注意：although/though 引導(dǎo)的從句不能與but連用，但可與yet, still連用。

　　五、引導(dǎo)目的狀語從句的從屬連詞有so that和in order that(以便，為了)等。

　　The teacher spoke loudly so that /in order that we could hear him clearly.

　　六、引導(dǎo)結(jié)果狀語從句的從屬連詞有：so that(結(jié)果是)和so/such…that…(如此…以至于)等。

　　It was very cold, so that the water in the bowl froze.

　　He got there so early that he got a good seat.

　　It is such a heavy box that nobody can move it.

　　七、引導(dǎo)比較狀語從句的從屬連詞有： as…as…(與……一樣),not as/so… as…(不及，趕不上),和than(比)等。

　　I know you better than she does.

　　He works as carefully as she.

　　I can’t run as/so fast as you.

　　八、引導(dǎo)名詞性從句的從屬連詞有：that和 if/whether(是否)等。

　　We know that the earth goes around the sun.(賓語從句)

　　I wonder if he has received my e-mail. (賓語從句)

　　Whether he’ll go there hasn’t been decided.(主語從句)

　　注意：在時間狀語從句和條件狀語從句中，如果主句是將來時，從句要用一般現(xiàn)在時。

　　I’ll go on with the work when I come back tomorrow.

　　He won’t come unless he is invited.