背信弃义：指故意欺骗、不诚实行事，违背诚信原则。
conceal one's true motives from especially by elaborately feigning good intentions so as to gain an end
同义词： bamboozle / snow / hoodwink / pull the wool over someone's eyes / lead by the nose
... 假兜(衣服上的)dummy pocket 假花artificial flowers 弄虚作假play false ...
... flummox 使混乱 play false 作弊 pull the wool over someone's eyes 欺骗某人,蒙蔽某人...
[play false] 用假的冒充真的或真的里头搀上假的 [what was make-believe has become reality;preterce(pretending) may become reality(truth)] 本来是想作假,结果竟成了真事 ..
Play it true or false, I make friends with only one thing: integrity.
管它玩的真假虚伪，我只有一样东西交朋友：诚信。
Life is like a play, by acting, not false, every minute of every little thing, you can deduce The imprint is engraved on my heart.
人生如戏，全靠演技，一点儿不假，每一分每一秒每一件小事，你都可以演绎得刻骨铭心。
If you play them false in this matter, they will not trust you again.
假若你在这件事上欺骗他们，他们便不会再信任你了。
And Kanye's attempts at expressing wide-eyed astonishment over his success play false now that he's throwing diva tantrums.
When they play him false, he refuses to quash them while he still can.
The disappointing scare campaign by Environmental Working Group promotes false fears about cleaning products, which play an essential role in our daily lives.
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