Dinosaurs rapidly became extinct about 65 million years ago as part of a mass extinction known as the K-T event, because it is associated with a geological signature known as the K-T boundary, usually a thin band of sedimentation found in various parts of the world. (K is the traditional abbreviation for the Cretaceous, derived from the German name Kreideieit). ( TPO42, 60)

　　abbreviation /ə'brivɪ'eʃən/ n. 简略，缩短

　　derive /dɪ'raɪv/ v. 获得，得到;源自，源于

　　大家自己先读，不回读，看一遍是否能理解

　　Dinosaurs rapidly became extinct about 65 million years ago (as part of a mass extinction) (known as the K-T event),(because it is associated with a geological signature) (known as the K-T boundary), (usually a thin band of sedimentation found in various parts of the world). (K is the traditional abbreviation for the Cretaceous, (derived from the German nameKreideieit)).( TPO42, 60)

　　托福阅读长难句100句分析：

　　这个句子的主干就是：

　　Dinosaurs rapidly became extinct about 65 million years ago

　　修饰一：(as part of a mass extinction) ，介词短语

　　中文：成为大灭绝事件的一部分

　　修饰二：(known as the K-T event) ，非谓语动词

　　中文：称之为K-T事件

　　修饰三：(because it is associated with a geological signature) ，从句

　　中文：因为它与地质学上的标签有联系

　　修饰四：(known as the K-T boundary) ，非谓语动词

　　中文：称为之K-T边缘

　　修饰五：(usually a thin band of sedimentation found in various parts of the world) ，同位语

　　中文：K-T边界通常是一块在世界各地都能找到的薄薄的沉积带

　　修饰六：(derived from the German name Kreideieit)，非谓语动词

　　中文：源自德国名字kreidezeit

　　托福阅读长难句100句参考翻译：

　　大约在6500万年前，恐龙迅速地灭绝，成为K-T大规模灭绝事件的一部分，被称作K-T是因为它与地质学上的标签K-T边界有关，K-T边界通常是一块在世界各地都能找到的薄薄的沉积带。(K在惯例上是白垩纪Cretaceous的缩写，源自德国名字kreidezeit)

　　这个句子的主要修饰成分就是从句、非谓语动词和同位语，大家务必想清楚，每一个修饰成分修饰的是什么，才能看清楚这个句子的结构。