都说托福阅读部分文章有难度，其实这种难度很多时候来自于文章中的长难句。这些句子结构复杂内容繁多，考生如果无法快速正确地看懂它们必然会影响对文章的理解和解题效率。所以下面小编就为大家带来托福阅读长难句的精选汇总和深度解析，为大家提供学习指点和启发。
托福阅读长难句实例分析原句案例：
Scientists felt that they could get an idea of how long the extinctions took by determining how long it took to deposit this one centimeter of clay and they thought they could determine the time it took to deposit the clay by determining the amount of the element iridium ( Ir ) it contained.
词汇讲解：
extinction / k'st k n/ n. 灭绝，绝种 ; 熄灭
deposit /d 'p ɑ z t/ v. 将 ( 钱 ) 存入银行 ; 付 ( 定金 ) ; 放下某物 ; 使 ( 淤泥等 ) 沉积
clay /klei/ n. 粘土
结构划分：
Scientists felt that they could get an idea ( of how long the extinctions took ) ( by determining ) ( how long it took to deposit this one centimeter of clay ) and they thought they could determine the time ( it took to deposit the clay ) ( by determining the amount of the element iridium ( Ir ) ) ( it contained. )
深度分析：修饰一： ( of how long the extinctions took ) ，介词短语
中文：灭绝所用的时间
修饰二： ( by determining ) ，介词短语
中文：通过确定
修饰三： ( how long it took to deposit this one centimeter of clay ) ，从句
中文：这层一厘米黏土层的沉积时间
修饰四： ( it took to deposit the clay ) ，从句，修饰 time
中文：这层黏土层的沉积时间
修饰五： ( by determining the amount of the element iridium ( Ir ) ) ，介词短语
中文：通过确定黏土层包含铱的含量

修饰六： ( it contained. ) ，从句，修饰 iridium
中文：它 ( 黏土层 ) 所包含的
参考翻译：科学家感觉他们可以通过确定这层一厘米黏土层的沉积时间就可以知道灭绝所用的时间，而他们认为可以通过确定黏土层包含铱的含量能确定它 ( 黏土层 ) 所沉积的时间。
托福阅读中的长难句虽然会对考生造成一定的干扰，但只要考生具备了快速看懂理解它们的能力，其实长难句也并非难以应对，希望本文内容能够帮助大家提升阅读实力拿到高分好成绩。