高中英語語法詳解:連詞(2)

　　4.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.

　　5.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)

　　6. 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.

　　7.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。

　　8.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。

　　9.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.

　　10.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.

　　11.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.

　　12.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.