It's based on, you know, you know, the primary documents, in many cases primary sources.

它是基于，你知道，呃，主要文件，在许多情况下是主要来源。

It's based on, you know, you know, the, uh, primary documents, in many cases, primary sources.

它是基于，你知道，呃，主要文件，在许多情况下是主要来源。

Some seem almost too breathtaking to be true—but every claim is referenced and backed up by links to research and primary documents.

有些事例甚至有些不可思议——不过每个引例都有来源说明，并由各类学术文献及基础理论支持。

Primary documents, and primary sources. Let's explain these terms with secondary sources. Let's say you're doing a research paper on Beethoven and you're researching what his diet was, what he ate.

主要文件，和主要来源。让我们用二级来源来解释这些术语。假设你在做一篇关于贝多芬的研究论文，你在研究他的饮食，他吃了什么。