重点句型
1. It doesn't make much of a difference whether a teacher speaks British or American English.
老师是讲英国英语还是美国英语是没有多大区别的。
2. Americans use a flashlight, while for the British, it's a torch.
美国人把手电筒称作flashlight，而英国人则叫torch。
3. When the Irish writer George Bernard Shaw made the famous remark that the British and the Americans are two nations divided by a common language, he was obviously thinking about the differences.
当爱尔兰作家乔治•萧伯纳讲那句名言——英国和美国是被同一种语言分开的两个民族时，他显然想到了它们的区别。
4. But it has also led to lots of American words and structures passing into British English, so that some people now believe that British English will disappear.
但是这也导致了许多美国英语单词和结构传入英国英语,以至于现在有一些人相信英国英语将要消失。

句型探究
1. It doesn't make much of a difference whether a teacher speaks British or American English.
老师是讲英国英语还是美国英语是没有多大区别的。
本句为主从复合句，it 为形式主语，whether 引导的从句为真正的主语。
It doesn't matter whether you will go or not.
你去不去都没关系。
whether 作“是否”讲时，引导名词性从句。
The problem is whether it is still useful.
问题是这是否仍然有用。
whether, if
二者引导宾语从句时可互换。
whether 可引导表语从句及同位语从句，if不能。
whether 引导的主语从句可位于句首或句尾，if 引导的主语从句只能位于句尾。
whether 可与动词不定式连用，if则不能。
She stood in the doorway, unable to decide whether to go in.
她站在门口，拿不定主意是否进去。

2. Americans use a flashlight, while for the British, it's a torch.
美国人把手电筒称作flashlight,而英国人则叫它torch。
句中while是并列连词，连接并列句，意为“然而，而”，此处表示对比，并含有轻微的转折意味。
在……过程中，在……期间 (=when)
while虽然，尽管 (=though)
只要 (=as long as)
Someone came to see you while you were out.
你出去时，有人来找过你。
There will be life while there is water and air.
只要有水和空气，就会有生命。
While he was right, few people would follow him.
虽然他是正确的，但是没有几个人愿意听他的。
注意：while 引导让步状语从句必须置于该从句的句首。

3. The other two areas in which the two varieties differ are spelling and pronunciation.
这两种英语另外两个领域的区别是拼写和发音。
本句为主从复合句,in which 引导定语从句，修饰areas。
介词+关系代词引导定语从句的选择：
根据从句谓语动词的搭配习惯：
This is the dictionary/on which I spent 50 yuan./for which I paid 50 yuan./from which I learnt a lot./about which he often talks.
根据先行词的搭配习惯：
I remember/the day on which I joined the league./the days during which I lived there./the month in which I stayed there.
介词可后移，此时关系词可省略：
The person/to whom we'll write./we'll write to.

4. When the Irish writer George Bernard Shaw made the famous remark that the British and the Americans are two nations divided by a common language,he was obviously thinking about the differences.
当爱尔兰作家乔治•萧伯纳讲那句名言——英国和美国是被同一种语言分开的两个民族时，他显然想到了它们的区别。
本句为主从复合句，when 引导了时间状语从句,在此从句中又含有that引导的同位语从句。
同位语从句一般跟在某些名词(如：fact, idea, news, promise, information, message等)的后面，用以说明或解释前面的名词。引导同位语从句的连接代词that，连接副词how, when, where等。
I have no idea when he will be back.
我不知道他何时回来。