Retropulsion
n. 后退\\n[医] 后退, 后退步态, 后冲步态
🗣️ 情景例句
You'd better watch your step or you'll get into trouble again.
你最好留点儿神， 免得再惹麻烦。
Action speak louder than words.
事实胜于雄辩。
as the wave leaves the particles behind back to its starting point again.
当波浪把微粒留在身后时又回到出发点。