语法专题8状语从句讲义.ppt

语法专题八　状语从句 状语从句在句中作状语，修饰主句中的动词、形容词或副词等。状语从句放在主句之前时，常用逗号分开；放在主句之后时，一般不用逗号。状语从句按其意义和作用可分为时间、条件、原因、让步、目的、结果、方式、比较、地点等9种。 1．时间状语从句 (1)时间状语从句常用的连词有when, as, while, before, after, since, till(until), as soon as, hardly...when..., no sooner...than, the moment等。 (2)时间状语从句一般不用将来时，因此，主句若为将来时，时间状语从句要用一般现在时。 (3)连词when, while, as都表示“当……的时候”，但是when引导的从句的动作和主句的动作可以同时发生，也可以先后发生；用as, while时则强调主句和从句的动作同时发生。 (4)till(until)表示“一直到……”时，主句和从句都用肯定式；表示“直到……才……”时，主句用否定式，从句用肯定式。 (5)as soon as和the moment引导的从句表示“一……就……”；用no sooner...than和hardly...when引导的从句表示“一……就……”。主句中的动词一般用过去完成时，从句用过去时；而且主句一般倒装，把助动词had提到前面。 2．原因状语从句 原因状语从句常用because, since和as引导。 3．地点状语从句 地点状语从句常用where, wherever等连词引导，注意不要和where引导的定语从句相混淆。 4．条件状语从句 条件状语从句用if, unless(if...not), as(so) long as(只要)等词引导，如果主句是将来时，条件状语从句用一般现在时表示。如： As_long_as I live, I shall work hard. 5．让步状语从句 让步状语从句由although(though), as, even if, however, whatever, no matter who(how...)等词引导。如： Clever as he is, he doesn’t study well. 注意：由as引导的让步状语从句，须将作表语的形容词或名词(名词前不用冠词)放在句首。 6．结果状语从句 结果状语从句一般由so, so that, so...that, such...that引导，放在主句之后。 7．目的状语从句 目的状语从句常由so...that, so that, in order that等引导，放在主句之后。 8．方式状语从句 方式状语从句放在主句之后，用as, just as, as if, as though等引导。as if和as though引导的从句一般用虚拟语气。但如果从句中所陈述的情况很可能实现，也可用陈述语气。 9．比较状语从句 比较状语从句常由as...as, than, not so...as..., the more...the more...等词引导。比较从句部分常是省略句。如： I know you better than he does. 1.(2009·重庆)Peter was so excited ______ he received an invitation from his friend to visit Chongqing. A. where　　　　 　 　　 B. that C. why D. when 3．(2009·浙江)The medicine works more effectively ______ you drink some hot water after taking it. A. as B. until C. although D. if 5．(2009·天津)I travel to the Binhai New Area by light railway every day, ______ do many businessmen who live in downtown Tianjin. A. as B. which C. when D. though 7．(2009·成都毕业班诊断)It matters little who does it ______ it is done, for you see, we are short of hands now. A. as long as B. as far as C. as early as D. as soon as 9．(2009·南京调研)We need to