1、第 11 讲 名词性从句1. It is uncertain _ side effect the medicine will bring about, although about two thousand patients have taken it. (2010浙江卷) A. that B. what C. how D. whether 【答案及解析】1. B考查主语从句引导词。句意:这种药将会带来什么样的副作用还不确定,虽然已有大约两千人在吃这种药。it为形式主语,_ side effect the medicine will bring about为真正的主语。还原句子: the me
2、dicine will bring about_ side effect,side effect前缺少一个修饰词,故用what。2. Is there any possibility _ you could pick me up at the airport? No problem. (2009浙江卷) A. when B. that C. whether D. what【答案及解析】2. B考查同位语从句的引导词。句意为:“你有可能到机场来接我吗?”“没问题。”you could pick me up at the airport是possibility的具体内容,故是同位语。又因这个从句不
3、缺任何句子成分,故用that引导。引导名词性从句的连接词 名词性从句相当于名词,可分别作主句的主语、表语、宾语和同位语。因此,名词性从句分为主语从句、表语从句、宾语从句和同位从句。1连接代词:who, whose, whom, what, which。有词义,在从句中充当成分,如主语、表语、宾语或定语等。2连接副词:when, where, why, how。有词义,在从句中充当成分,作状语。3连接词:that, whether, if, as if。that 无词义,在从句中不充当成分,有时可省略;if (whether), as if虽有词义,但在从句中不充当成分。注意:名词性从句的语序陈
4、述语序他是怎么成功的仍然是个谜。How was he successful is still a puzzle. ()How he was successful is still a puzzle. ()主语从句的用法1主语从句在复合句中作主语。如:Who_will_go is not important. 2用it作形式主语,主语从句放在句末。如:It doesnt matter so much whether_you_will_come_or_not. 3that引导主语从句时,不能省略。如: That_he_suddenly_fell_ill_last_week made us surp
5、rised. 表语从句的用法1表语从句在复合句中作表语,位于系动词之后。如:The question was who_could_go_there. 2引导表语从句的连接词that有时可省去。My idea is (that)_we_can_get_more_comrades_to_help_in_the_work. 宾语从句的用法 1宾语从句在复合句中作宾语。引导宾语从句的连词that一般可省略。如:I hope (that) everything is all right. 2介词之后的宾语从句,不可用which或if连接,要分别用what或 whether。如:Im interested
6、 in whether youve finished the work. 同位语从句的用法同位语从句在句中作某些抽象名词的同位语,说明该名词的具体内容。这类抽象名词有:I have no idea when he will be back. The fact that he had not said anything surprised everybody. 易错易混点1whether与if的区别 (1)只能用if的情况 宾语从句是否定句时,只用if,不用whether。 如: I wonder if it doesnt rain. 引导条件从句时,只能用if,而不能用whether。如: P
7、lease come to see me if_you_have_time. (2)只能用whether的情况 用if 会引起误解,就要用whether。如: Please let me know whether you want to go. (此句如果把whether改成if,容易当成条件句理解) 宾语从句中的whether 与or not直接连用,就不能换成if;不直接连用,可换。如: I dont know whether_or_not the report is true. I dont know whether/_if the report is true or not. 介词后的
8、宾语从句要用whether引导。whether 可与不定式连用。whether也可引导主语从句、表语从句、同位语从句,还可引导让步状语从句,以上均不能换成if。如: It depends on_whether we have enough time. They dont know whether_to_go there. 2名词性从句中主句和从句的主谓一致 (1)主语从句作主语相当于单数第三人称作主语,谓语动词用单数。 (2)如果由and 连接两个或两个以上的主语从句作主语时,谓语动词用复数。 (3)由两个或多个连接词引导一个主语从句,谓语动词用单数。 When_they_will_start
9、_and_where_they_go have not been decided yet. When_and_where the party will be held has not been decided yet. 3. 疑问词 ever 和 no matter 疑问词的区别 (1)疑问词 ever可引导名词性从句,在主从句中要充当一定的成分。如: Whoever breaks the rule must be punished. (作主语) (2)疑问词 ever还可引导让步状语从句。如: Whoever breaks the rule, he must be punished. (3)
10、no matter 疑问词只能引导让步状语从句。 No_matter_who breaks the rule, he must be punished. 4. 同位语从句和定语从句的区别 定语从句是先行词的修饰语,它不涉及先行词的具体内容。定语从句中that起连接作用,且充当句子成分,作宾语时可省略。 同位语从句表明中心词的具体内容。that在同位语从句中不作任何成分,只起连接作用,无具体含义,且不可省略。如: We expressed the hope that_they_had_expressed. (定语从句) We expressed the hope that_they_would_
11、come_toChina_again. (同位语从句)5. it作形式主语的常用句型 It is possible/important/necessary/clear/true that很可能/重要的是/必要的是/很清楚/很对 It is said/ reported/believed that据说/据报道 It has been announced/declared that已经通知/宣布 It seems/appears/happensthat似乎/显然、明显/碰巧 It is no wonder that并不奇怪/无疑 Its a pity/a shame/a good idea/a fact/common knowledge (众所周知)/a common saying (俗话说)