I would like to place on record my sincere thanks.

我要公开表示诚挚的谢。

He is a wholehearted friend of mine.

我的诚挚的朋友。

Her mild but speaking countenance manifested a strong sympathy in the anticipated agony of the suppositious sufferer.

她那温和而诚挚的脸上对这位假想受难者预料中的难流露出极大的同情。

Please accept our sincere condolences.

请接受我们诚挚的慰唁。