I sent my heartfelt apology to those who I had hurt.

我向遭受伤害的人表示由衷的歉意。

The president extended his heartfelt sympathy to those who lost their families in the earthquake.

总统向那些在那次地震中失去家人的人表示衷心的同情。

We would like to express our heartfelt thanks for your valuable suggestions.

我们衷心感谢您的宝贵建议。

Please accept my heartfelt apologies.

请接受我由衷的歉意

The recipient of the prize gave a heartfelt acceptance speech.

获奖人发表了由衷的感言。

My heartfelt sympathy goes out to all the relatives.

我对所有的亲属表示衷心的慰问。

Our heartfelt sympathy goes out to the victims of the war.

我们对战争的受害者表示由衷的同情。

Ladies and gentlemen, on behalf of our government, I'd like to extend a sincere welcome and heartfelt gratitude.

女士们、先生们，我谨代表我国政府，向各位表示诚挚的欢迎和衷心的感谢。

I would like to take this opportunity to express my heartfelt gratitude to you for your help when I was in difficulty.

借此机会，我谨对您在我最困难的时候给予我的帮助表示衷心的感谢。

A heartfelt welcome to everyone!

衷心欢迎你们的到来！