proof n. 证明，证据
〔辨析〕指可以表明某事物真实性的信息、文件等。

《柯林斯高阶英汉双解学习词典》的例句：
Proof of postage will not be accepted as proof of receipt.
邮资单据不能当作收据。

《牛津词典》的例句：
Can you provide any proof of identity ?
你能提供什么身份证明吗？

Keep the receipt as proof of purchase .
保存收据，作为购物证明。

There is no proof that the knife belonged to her.
没有证据证明那把刀子是属于她的。

These results are a further proof of his outstanding ability.
这些成果进一步证明了他的杰出才干。