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with a pat; with a tap; with a clap; with a slap; with a smack
with a pop; with a crack
casually (throw); carelessly
generously (give)
肩をぽんとたたかれた。
I was patted on the shoulder.
彼はぽんとお金を置いて立ち去った。
He put down the money with a slap and walked away.
子供の頭をぽんとなでて励ました。
I patted the child on the head and encouraged them.