成考2014年成人英语三级语法知识：词法分析（四）

　　6. 引导条件状语从句的从属连词有：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.引导原因状语从句的从属连词有 because, as, since等。

　　because“因为”语气最强,回答why提问时只能用because，其引导的从句可放在句首或句末;as“由于”、since“既然”语气不如because强，引导的从句常置于句首;for是并列连词，语气最弱，对前面分句加以解释或补充说明，其引导的分句常置于句末且用逗号隔开。

　　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与 so不能同时使用。

　　8.引导让步状语从句的从属连词有：although/though(虽然，尽管), 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 引导的从句不能与but连用，但可与yet, still连用。

　　9.引导目的状语从句的从属连词有so that和in order that(以便，为了)等。

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

　　10.引导结果状语从句的从属连词有：so that(结果是)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.引导比较状语从句的连词：as…as…(与…一样),not as/so… as…(不如),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.

　　注意：在时间状语从句和条件状语从句中，如果主句是将来时，从句要用一般现在时。

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

　　He won’t come unless he is invited.