外教一对一 http://www.yangjiajiao.com 英语长难句分析
1. Pumas are large, cat-like animals which are found in America.
美洲狮是一种体形似猫的大动物，产于美洲。
这个句子比较简单：主系表结构;稍稍复杂的就是有一个定语从句而已。
2. When reports came into London Zoo that a wild puma had been spotted forty-five miles south of London, they were not taken seriously.
当伦敦动物园接到报告说，在伦敦以南45英里处发现一只美洲狮时，这些报告并没有受到重视。
第一层分析：
这个句子主干其实就三个成分：时间状语(从句)，主语+谓语(被动语态)+方式状语。
第二层分析：
但状语从句比较复杂：
When reports came into London Zoo that a wild puma had been spotted forty-five miles south of London,
状语从句结构：when(引导词，不做成分)+主语+谓语+状语+同位语从句(作主语reports的同位语)
第三层分析：
这是一个同位语从句(名词性从句作同位语)
that a wild puma had been spotted forty-five miles south of London
从句的结构比较简单：that(引导词，不做成分)+主语+谓语+状语
3. However, as the evidence began to accumulate, experts from the Zoo felt obliged to investigate, for the descriptions given by people who claimed to have seen the puma were extraordinarily similar.
可是，随着证据越来越多，动物园的专家们感到有必要进行一番调查，因为凡是声称见到过美洲狮的人们所描述的情况竟是出奇地相似。
第一层分析：
只要你愿意按照步骤逐步来做，第一层分析总是很简单：
这是一个并列句(for为并列连词)：as...to investigate, for the description ... similar.
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外教一对一
第二层分析：for前的句子
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as the evidence began to accumulate, experts from the Zoo felt obliged to investigate,
现在看是不是简单多了?结构为：
时间状语(从句)，主语+系动词+表语
第三层分析：for前的句子
as the evidence began to accumulate
as(引导词，不做成分)+主语+谓语+宾语
简单了吧?
第二层分析：for后的句子
the descriptions given by people who claimed to have seen the puma were extraordinarily similar
大主干分析也是比较简单：主语+系动词+表语
第三层分析：for后的句子
descriptions given by people who claimed to have seen the puma
这部分就是given分词短语作descriptions的后置定语。
第四层分析：for后的句子
who claimed to have seen the puma
这是一个定语从句，修饰前面的people。其结构为：
who(引导词，作主语)+谓语+宾语
文章来源：www.yangjiajiao.com
英语长难句分析
