名词性从句名词性从句（主语、表语、宾语、同位语从句）（一） 主语从句1． 定义：用作主语的从句叫做主语从句。2． 2． 构成：关联词 +简单句3． 3． 引导主语从句的关联词有三类：4． (1) 从属连词 that 。 如：That they were in truth sisters was clear from the facial resemblance between them. 很明显，她们确是亲姐妹，她们的脸型很相似。(2) 从属连词 whether 。如：Whether he ’ll come here isn’t clear. 他是否会来这里还不清楚。(3) 连接代词 who, whom, whose, what, which, whoever, whatever, whichever 连接副词 where, when, how, why。如：What she did is not yet known. 她干了什么尚不清楚。解释：1． 主语从句能用it作形式上的主语。常以it作形式主语的句型有：A. It+be+ 形容词 (obvious, true, natural, surprising, good, wonderful, funny, possible, likely, certain, probable, etc.)+that从句。如：It is certain that she will do well in her exam. 毫无疑问她考试成绩会很好。B. It+be+ 名词词组 (no wonder, an honour, a good thing, a pity, no surprise, etc.)+that从句。如：It ’s a pity that we can’t go. 很遗憾我们不能去。 。C.It+seem, happen等不及物动词及短语+that从句。如：It seems that Alice is not coming to the party at all. Alice似乎不来参加晚会。D.It+doesn ’t matter (makes no difference, etc.)+ 连接代词或连接副词引起的主语从句。如：It doesn’t matter whether she will come or not. 她是否来这无关紧要。F. 当 that引导的主语从句出现在疑问句中时，要以 it作形式主语， 而把主语从句后置。 如：Does it matter much that they will not come tomorrow? 他们明天不来很要紧吗？G. 当主语从句出现在感叹句中时，要以it作形式主语，而把主语从句后置。如：How strange it is that the children are so quiet! 孩子们这么安静真奇怪！2．注意连接代词whoever, whatever, whichever等引导主语从句的含义Whoever comes will be welcome. (whoever=the person who) 来的人将受到欢迎。（二） 表语从句1． 定义：用作表语的从句叫做表语从句。2． 构成：关联词 +简单句3． 引导表语从...
