His bona fides was questioned.

人家怀疑他的诚意.

《现代英汉综合大词典》

His bona fides are unquestionable.

他的诚意不容置疑.

辞典例句

In doing this, it requires your bona fides and devotion.

做这件事需要你的真诚和投入.

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Bona fides is my first choice of making friends.

真诚是我交朋友的首选.

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Respondents must be enabled to check without difficulty the identity and bona fides of the Researcher.

被访者必须能够毫无困难地检查研究人员的身份和真实性.

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