高中英语语法讲解素材:名词性从句

高中英语语法讲解——名词性从句 一、名词性从句的三类连词 名词性从句包括主语从句，表语从句，宾语从句和同位语从句。根据这些从句的共同特性，名词性从句的连词主要可以分成三类：that, if/ whether和wh-(疑问词)。 1．如果一个陈述句被用来作为另一个句子的主语、表语、宾语或同位语，那么我们一般要用that作为连词。that本身在句子中没有意思，只起连接作用。 eg. 陈述句：Science is developing very fast. 主语从句：It is known to all that science is developing very fast. 表语从句：The fact is that science is developing very fast. 宾语从句：Everyone knows that science is developing very fast. 同位语从句：The fact that science is developing very fast is known to all. 2．如果一个一般疑问句被用来作为另一个句子的主语、表语、宾语或同位语，那么我们要用whether或if作为连词。whether/ if在句子中的意思是“是否”。变成名词性从句后，原来的疑问句的词序要改成陈述句的词序（主语+谓语）。 eg. 一般疑问句：Shall we have a meeting this afternoon? 主语从句：Whether we shall have a meeting this afternoon hasn’t been decided yet. 或：It hasn’t been decided yet whether we shall have a meeting this afternoon. 表语从句：The question is whether we shall have a meeting this afternoon. 宾语从句：Do you know whether we shall have a meeting this afternoon? 同位语从句：None of us