雅思基础阅读难句解析-平行结构(15)

　　雅思基础阅读难句解析-平行结构

　　15. Human beings have distinguished themselves from other animals, and in doing so ensured their survival, by the ability to observe and understand their environment and then either to adapt to that environment or to control and adapt it to their own needs.

　　结构：本句只有一个谓语动词have，接两个并列的过去分词distinguished和ensured。by引导的方式状语后面并列了多个动词不定式to observe and understand/to adapt to/to control and adapt it to，作为ability的修饰成分。

　　翻译：人类已经将自己与其他动物区分开来，并且通过这样做来确保自己的生存，所依靠的就是通过观察和理解周围的环境，然后适应，控制并且改造该环境，使其适合自己需要的能力。