Unit 1 A land of diversity Section Ⅲ Grammar-名词性从句（主语从句、宾语从句和表语从句） 语法图解探究发现①Exactly when the first people arrived in what we now know as California, no one really knows.②However, it is likely that Native Americans were living in California at least fifteen thousand years ago.③Scientists believe that these settlers crossed the Bering Strait in the Arctic to America by means of a land bridge which existed in prehistoric times. ④That is why today over 40% of Californians speak Spanish as a first or second language.⑤It is believed that before long the mix of nationalities will be so great that there will be no distinct major racial or cultural groups, but simply a mixture of many races and cultures.[我的发现](1)以上各句皆为主从复合句，句中用了相当于名词作用的从句(即名词性从句)在句中充当成分。(2)名词性从句在句中可作介词的宾语(句①)，动词的宾语(句③)。(3)名词性从句在句中可作主语，且可用 it 作形式主语，真正的主语从句置于句末(句②、⑤)。(4)名词性从句在句中可作表语(句④)。一、主语从句、宾语从句和表语从句的定义及特点(一)主语从句主语从句是指在句中作主语的从句，位置与陈述句的主语相同。Whether the sports meet will be held is not certain now.运动会是否将举行现在不能确定。 How the book will sell depends on its author.这本书销售如何取决于作者本人。Where we shall have the meeting makes no difference.我们在哪儿开会都无所谓。[名师点津] 若主语部分结构较长，可以使用形式主语 it，把真正的主语从句放于后面。That she will do well in her exam is certain.＝It is certain that she will do well in her exam.她在考试中会做得好，这是确定无疑的。(二)宾语从句1．作及物动词的宾语Everyone knows that the earth is made up of matter.每个人都知道地球是由物质构成的。2．作介词的宾语如：besides that ...“除……之外”；but that ...“若不是……”；except that ...“除了……”；in that ...“在于...
