The authors documented an annual drop of as many as 120,000 cases of heart disease, 66,000 instances of stroke and 99,000 heart attacks caused by high blood pressure after a 3-g-per-day reduction in salt.
出自-2013年6月阅读原文
The team at Frontpoint addresses the issue in a blog on its site, citing their own jam protection software and claiming that there aren't any documented cases of successful jam attack since the company began offering wireless security sensors in the 1980s
2016年12月四级真题（第一套）阅读 Section B
英语六级真题
Educators may fear that children hearing two languages will become permanently confused and thus their language development will be delayed ;this concern is not documented in the literature.
出自-2013年12月阅读原文
In 2011 they released a landmark study titled "Academically Adrift", which documented the lack of intellectual growth experienced by many people enrolled in college.
2015年12月六级真题（第一套）阅读 Section C
Psychologists have documented children lying as early as the age of two.
2019年12月六级真题（第一套）阅读 Section C
柯林斯高阶英汉双解学习词典释义
N-COUNT
文件;公文;文献;证件
A document is one or more official pieces of paper with writing on them.
A document is a piece of text or graphics, for example a letter, that is stored as a file on a computer and that you can access in order to read it or change it.