unfaithful
adj. 不忠实的；不诚实的；不准确的
例句
Have you ever been unfaithful to him?
你对他是否有过不忠行为？
《牛津词典》
He vowed to wreak vengeance on his unfaithful, thieving wife.
他发誓要报复对自己不忠、爱偷东西的妻子。
《柯林斯英汉双解大词典》
She was shocked by the discovery that he had been unfaithful.
她发觉他不忠时感到非常震惊。
