Our friendship has stood the test of time for we've known each other for more than 20 years.

我们的友谊经受了时间的考验，因为我们已经认识超过20年了。

youdao

Musharraf indicated that bilateral friendship has withstood the test of time and China is Pakistan's sincere and reliable friend. Pakistan is full of confidence about bilateral relations.

穆沙拉夫表示，巴中友谊经历了时间的考验，中国是巴基斯坦真诚、可信赖的朋友，巴方对巴中关系充满信心。

youdao

This is a serious test of our friendship.

这是对我们友谊的一次重大考验。

youdao

But on the whole the results of that sort of litmus test of friendship are much more positive than negative.

BBC: Breakfast with Frost

And especially in a democratic society, friendship was seen as a test case of whether or not democracy was working.

NPR: Lincoln and Douglass Shared Uncommon Bond

So Douglass especially promoted, championed his interracial friendship as a kind of test case, on-the-ground example of how democracy could work, and in his hope, an inspiration for others in the United States.

NPR: Lincoln and Douglass Shared Uncommon Bond