n.背信，背叛

原形：perfidy复数：perfidies

He was guilty of perfidy, betraying his comrades in the heat of battle.
他在战斗中背信弃义，背叛了他的战友。
The traitor's perfidy was exposed when he tried to sell military secrets to the enemy.
当他试图向敌人出卖军事机密时，他的背信行为被揭发了。
His perfidious actions during the negotiation led to the breakdown of the deal.
他在谈判中的狡诈行为导致交易破裂。
She felt betrayed by her partner's perfidy, as they had promised to be loyal to each other.
她因伴侣的背信而感到被背叛，他们曾承诺彼此忠诚。
The perfidiously cunning politician managed to deceive everyone with his false promises.
这位诡计多端的政治家用虚假的承诺欺骗了所有人。
The spy's perfidy was discovered when his coded messages were intercepted.
当他的密码信息被截获时，间谍的背信行为暴露无遗。
The perfidy of the betrayer left a deep scar on the victim's heart.
背叛者的背信使受害者的心灵深受伤害。
The perfidiously unjust law favored the wealthy over the poor.
这项不公正的法律偏袒富人，对穷人背信忘义。
Her perfidiously false smile hid the anger and resentment she felt towards him.
她那虚伪的笑容掩盖了她对他愤怒和怨恨的真实情绪。
The company's perfidy in reneging on their contracts led to legal action from their clients.
公司背信弃义地撕毁合同，导致客户采取了法律行动。