adj.无懈可击的，不容置疑的，无可指摘的，无可怀疑的

His character is unimpeachable; he has never been known to lie or cheat.
他的品格无可挑剔；他从未被发现说谎或欺骗。
The witness's testimony was unimpeachable, as it was backed up by solid evidence.
证人的证词无可置疑，因为它有确凿的证据支持。
She holds an unimpeachable reputation in the academic community for her groundbreaking research.
她在学术界因开创性的研究享有无可质疑的声誉。
The judge deemed the juror's impartiality unimpeachable during the trial.
在审判过程中，法官确认了陪审员的公正性无可置疑。
The constitution stands as an unimpeachable cornerstone of our nation's legal framework.
宪法作为我们国家法律体系的基石，其权威无可动摇。
His commitment to honesty and integrity is unimpeachable, making him a role model for others.
他对诚实和正直的承诺无可置疑，使他成为他人的楷模。
The prime minister's commitment to environmental protection is an unimpeachable policy position.
首相对环境保护的承诺是其不可动摇的政策立场。
An unimpeachable argument requires facts, logic, and sound reasoning to convince the audience.
一个无可辩驳的论点需要事实、逻辑和合理的推理来说服听众。
Her leadership skills are unimpeachable, earning her the respect of her colleagues.
她的领导才能无可挑剔，赢得了同事们的尊重。
The authenticity of the artwork has been verified, making it an unimpeachable masterpiece.
这件艺术品的真实性得到了验证，使其成为无可争议的艺术杰作。