赤诚的英文：
absolute sincerity

参考例句：

They treat people with absolute sincerity.
他们赤诚待人。

absolute是什么意思：
adj. 绝对的；完全的；专制的
n. 绝对；绝对事物

This is absolutely a scratch.
这完全就是一通乱写。

The performances have been absolutely phenomenal.
表演绝对精彩。

It's absolutely no business of hers.
这件事与她毫不相关。

The use of cryotherapy is absolutely contraindicated.
冷冻治疗的应用是绝对禁忌的。

He ruled with absolute power.
他实行独裁统治。

sincerity是什么意思：
n. 诚挚

She‘s a sincere friend.
她是位忠实的朋友。

His sincereness moved me.
他的真诚打动了我。

Misfortune tests the sincerity of friends
患难见真情.

Misfortunes test the sincerity of friends
患难见友情

Misfortune tests the sincerity of friends.
患难见真情。