The letter closed with sincere greetings which I did not think referred to me, but the warden was sincere about the issue.

这封信结尾真诚的问候我认为不是跟我说的，但是那个监狱长对待此问题倒是很真诚的。

youdao

I say not flatteringly but with sincere conviction.

我说话不是奉承，而是心悦诚服。

《新英汉大辞典》

Poor fool, poor blind fool, I thought with sincere compassion, mugged by an invisible man!

可怜的傻瓜，又瞎又傻的可怜人，我满心同情的想，被一个看不见的人抢劫了！

youdao

"The message is if you are not going to be clean and sincere, if you are going to engage in criminal activity, if you are going to cooperate with the Taliban, we will hold you accountable."

VOA: standard.2010.05.28

Do we believe him in this respect, I mean an important question, do we believe him again, ? is he being sincere in this or is he using this as it were a kind of rhetoric ? with which to envelope himself?

我们相信他这番言论吗，我意指一个重要的问题，我们再次自问是否要相信他，他这么说时是否诚恳,或只是利用这类的修辞,来包裹自己？

耶鲁公开课 - 政治哲学导论课程节选

It is with sincere gratitude that I accept this Cesar Chavez Champions of Change Award.

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In a words-are-cheap world, deals are sealed with sincere smiles and straightforward signals.

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