show one's hand 不是“伸手”，但它其实是个固定短语，表示“摊牌，表明自己的计划或意图”。

【例句】
I won't show my hands until next week, so mum's the word!
我下周才摊牌，所以保密！

The negotiations will not make progress as long as they refuse toshow their hand.
他们要是不肯摊牌，谈判就不会有进展。