表扬信。

Letters of commendation.

这些罪犯因为救了狱监的命而被表扬，但是他们的英雄行为，只换来了治安官的表扬信而已。

The prisoners were credited with saving the guard's life, but for all their heroism, the convicts received nothing but congratulatory letters from the sheriff's department.

您作为壹个投资者和我们公司的合作己经有非常长一段时间了，我们想给您提供一个机会，您只把您与我们公司合作的经验写成一封介绍信（表扬信，证明）提交给我们，就有机会获得500美元的奖励。

Seeing that you have been an investor with our firm for quite some time, we would like to offer you an opportunity to submit a testimonial on your experience with us and get a chance to win $500!