第十一讲名词性从句
名词性从句的本质：3种句子充当4种成分 所谓名词性从句，就是把完整句子当作名词来使用，使之在另一个句子中充当某种成分。一般来说，名词在句中主要充当4种成分：主语、宾语、表语和同位语，于是便有了常说的4种名词性从句：主语从句、宾语从句、表语从句和同位语从句。相当于名词作用的句子有3类：陈述句、一般疑问句和特殊疑问句。因此，名词性从句可简单概括为这样一句话：名词性从句就是用3种句子分别充当另外一个句子的4种句子成分。这便构成了名词性从句的本质特征。
名词性从句 的引导词 连词that 连词whether/if 连接代词who， whom, what， which, whose； 连接副词 when, where， why, how
主语从句 特殊疑问句 对应的句 子类型 陈述句 一般疑问句 是否作成分 that在从句中不作成分 whether和if在从句中不作成分 who和what在从句中作主语、宾语或表语；whom在从句中作宾语；which在从句中作主语、表语或定语；whose在句中作定语。连接副词在从句中作状语 1.that引导的主语从句
(1)that引导主语从句时，在从句中不作任何成分，也没有词汇意义，但一般不可省略。 That the earth goes around the sun is known to us all. 众所周知，地球围着太阳转。
(2)that引导主语从句时可用it作形式主语，that不可省略。常见句式主要有以下几种：
①It＋be＋形容词(necessary, right, likely, unlikely, wrong, important, certain, clear, obvious, strange, normal等)＋that从句
It isn’t likely that I should accept such an offer as that. 我不可能接受像那样的帮助。
②It＋be＋名词(短语)(a pity, a shame, good news, a fact, an honour, a wonder, no wonder等)＋that从句
It’s no wonder that he didn’t want to go. 难怪他不想去。
③It＋be＋过去分词(said, told, heard, reported, decided, suggested, advised, ordered, remembered, thought, considered, well-known, announced等)＋that从句
It is decided that the meeting has been put off until next Monday. 会议被推迟到下周一已经定下来了。 [
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suggested/advised/ordered/requested/insisted/required ...＋that从句”结构中，从句谓语应用“(should＋)动词原形”。
It is suggested that you (should) spend more time in studying English. 建议你花更多的时间学习英语。
④It＋特殊动词或短语(seem, appear, happen, matter, turn out, occur to, make no difference等)＋that从句
It suddenly occurred to her that Joe was afraid of being alone. 她突然想到乔害怕独自一个人待着。 2．whether/if引导的主语从句
主语从句位于主句谓语动作前，表示“是