我们假设这是因为当你出石头时，你的手是个拳头，不可否认拳头比伸开的手掌(步)或是愤怒的手指(剪刀)更有气势。

We assume it's because it's a fist, which is undeniably more badass than an open-hand slap (paper) or angry pointing (scissors).

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玩家们把拳头握在手掌中，倒数3、2、1后伸手做出三种手势中的一种。 三种手势分别为：一只拳头（代表石头），伸开的手掌（代表布），以及两根手指（代表剪子）。

Players smack their fists into their palms and count to three before making one of three hand signals: a fist (rock), flat hand (paper) or two fingers (scissors).

youdao

在维琪奥桥(Ponte Vecchio)下面的桥墩旁边，有几欧元落入了一个吉普赛人伸开的手掌心里，最后以我丈夫签字放弃对一幢漂亮的旧田舍的所有权而告终，那是我们度假时的家。

A few Euros dropped into a gypsy's outstretched palm at the foot of the Ponte Vecchio, culminating in my husband signing away the title to a beautiful old farmhouse, our vacation home.

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