high five高高地举起五，也就是高举手掌，然后打对方的手，与某人庆祝或打招呼；相互高举胳膊击掌。

【例句】
The two friends high fived each other at the end of the game.
两个朋友在比赛结束时互相击掌。

At the time we naively thought that this day will last forever, so we high five vows to be together forever, never apart.
那时的我们天真地以为这样的日子会一直持续下去，所以我们击掌盟誓要一辈子在一起，永远也不分开。