I have to show you that our friend has proven that time, indeed has a beginning.

我得告诉你，我们的朋友证明了时间是有起点的。

The DNA cases proved this several times.

DNA 案例多次证明了这一点。

Writing was then independently invented just four (proven) times, in Mesopotamia, Egypt, China and Mesoamerica.

文字仅在美索不达米亚、埃及、中国和中美洲独立发明了四次（已被证实）。

He says " one country, two systems" has been tested and proved time and again, and there is no reason to change such a good system and it must be adhered to over the long run.

他说，“一国两制”是经过实践反复检验，这样的好制度，没有任何理由改变，必须长期坚持。

That is an astonishing statement and yet proven a thousand times every day of our lives. It expresses, in part, our inescapable connection with the outside world, the fact that we touch other people's lives simply by existing.

那是一个惊人的论断，在我们生活的每一天里被无数次证实。它指明我们与外部世界有无法脱离的联系，我们以自身的存在接触着他人的生命。

Yet while the US military has proven time and again it dominates the modern battlefield, it has historically had the exact same troubles that every other military has when it comes to fighting low-intensity counter-insurgency wars.

然而，尽管美军一再证明它在现代战场上占据主导地位，但从历史上看， 它在低强度平叛战争中遇到的麻烦与其他所有军队完全相同。