摊牌(tānpái)to have a showdown：lay one’s cards on the table

Usage:

“摊牌”本义是打牌时把自己的牌全部亮出来。比喻在最后时刻向对方亮出自己的主张或底细，也比喻公开最后的决定。
The original meaning of “摊牌”（ tānpái） is laying one’s cards on the table in card game. It is a metaphor of having a showdown at the last moment or making the final decision to the public.

Sentences：

1、Jìrán nǐ yǐjīng juédìng cízhí le, jiù jǐnzǎo gēn lǎobǎn tānpái ba.
既然你已经决定辞职了，就尽早跟老板摊牌吧。
Since you have made up your mind, you’d better tell your boss as soon as possible.

2、Guānyú jūnbèi wèntí, méi rén zhīdào zhèngfǔ shénme shíhou tānpái.
关于军备问题，没人知道政府什么时候摊牌。
For the armament, no one knows when the government will be ready for a showdown.

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