之前我们从比较对象标准，比较词判断，和比较对象的判断的三个方面分析了比较题。为了保证大家能够彻底掌握，我们今天再看一个相应的例题。
接下来的例题，我们依然按照统一的比较题解题步骤讲解：
1：根据比较词判断比较考点
2：判断比较词对不对
3：判断比较对象是否正确
例一：
Providing initial evidence that airports are a larger source of pollutionthan they were once believed to be, environmentalists in Chicago report thatthe total amount of pollutant emitted annually by vehicles at O’HareInternational Airport is twice as much as that which is being emitted annually by all motor vehicles in the Chicago metropolitan area.
(A) as much as that which is being emitted annually by all
(B) as much annually as is emitted by the
(C) as much compared to what is annually emitted by all
(D) that emitted annually by all
(E) that emittedannually compared to the
1 根据划线部分as much as判断此题考查比较考点。
2 判断比较词是否正确。
当compare to一起出现时，它不表示比较的意思，所以我们知道CD选项的比较词错误。
3 判断比较对象是否正确
补充知识：
1 根据比较题目的第二讲，我们知道A as…as B句型里面比较的是A和B，也就是两个as前后的内容。
2 AD 选项都出现that，我们先来补充一下它的用法。That通常作用引导定语从句的连接词，但是在比较句里面，它是代词，指代比较前面出现的相同的信息。
举例：
The shoes of men and women
这个表达有一些歧义，因为这里有两种可能的并列：鞋子和鞋子并列以及男人和女人并列。因为不同的并列就代表不同的意思，所以这里显然是有歧义的。
改正：
1 鞋子和鞋子并列
The shoes of men and shoes of women 进化为The shoes of men and those of women
用that指代前面出现的单数名词，用thoes指代前面出现的复数名词
2 男人和女人并列
The shoes of both men and women
A 选项比较的是the total amount of pollutant emitted annually by vehicles at O’Hare
International Airport is…句子和that which
is being emitted annually by all…。That指代前面的the total amount，所以前面是句子和后面的一个名词无法比较。排除
B 选项比较的是the total amount of
pollutantemitted annually by vehicles at O’HareInternational Airport is…和the total
amount is emitted by all 污染物总量有多少和污染物总量是由谁释放的这两件事情无法比较。排除
D 选项the total amount of pollutant emitted annually by vehicles at O’Hare
International Airport is…和the total amount of pollutant emitted annually by前后比较的分别是由O’Hare International Airport释放的污染物总量和由所有汽车释放的污染物的总量，显然两者可以比较
正确答案：D
S
