托福阅读高难度文章长难句实例解析：石油是有机物分解产物

　　Two additional kinds of evidence support the hypothesis that petroleum is a product of the decomposition of organic matter: oil possesses optical properties known only in hydrocarbons derived from organic matter, and oil contains nitrogen and certain compounds believed to originate only in living matter.

　　结构分析：

　　复合句。句子主干为：主语+谓语+宾语，宾语后有一个同位语从句;冒号后为主语的同位语。

　　句子分析：

　　Two additional kinds of evidence support the hypothesis that petroleum is a product of the decomposition of organic matter，其中，two additional kinds of evidence为主语，support为谓语，the hypothesis为宾语。that引导the hypothesis的同位语从句，其中，petroleum为主语，is a product 为系表结构;介词短语of the decomposition of organic matter作定语，修饰表语。本部分意思：还有另外两种证据能支持石油是有机物分解的产物这一假设。

　　(1)oil possesses optical properties known only in hydrocarbons derived from organic matter and (2)oil contains nitrogen and certain compounds believed to originate only in living matter

　　这两部分为主语Two additional kinds of evidence的同位语，对主语进行解释说明。

　　部分1中，oil为主语，possesses作谓语，optical properties作宾语。 过去分词短语known only in hydrocarbons作后置定语，修饰properties, derived from organic matter为后置定语，修饰hydrocarbons. 本句意思：石油具有光学特性，这些特性只有源自有机物的碳氢化合物中才有。

　　部分2中，oil为主语，contains为谓语，nitrogen and certain compounds为并列宾语。后置定语believed to originate only in living matter修饰compounds。本句意思：石油含有氮和某些化合物，人们认为这些化合物只能来源于有生命的物质。

　　参考翻译：

　　还有另外两种证据能支持石油是有机物分解的产物这一假设：一是石油具有光学特性，这些特性只有源自有机物的碳氢化合物中才有;二是石油含有氮和某些化合物，人们认为这些化合物只能来源于有生命的物质。