承诺那只是一时儿戏罢了
[chéng nuò nèi zhĭ shì yī shí ér xì bà le]
'Promise Is Just a Jest of That Time.' This indicates disillusionment with promises, perhaps from unfulfilled promises that have hurt the person. It implies that at one time promises were treated trivially, not sincerely intended but said casually without thought of keeping them.