to two-time
01
裏切る, 不貞を働く
to betray one's partner by secretly having an affair with someone else at the same time
例
She was devastated when she found out he had been two-timing her with her best friend.
彼女は、彼が彼女の親友と浮気していたことを知ったとき、打ちのめされた。
He thought he could get away with two-timing his girlfriend, but she eventually discovered the truth.
彼は彼女を二股かけて逃げ切れると思ったが、彼女は最終的に真実を発見した。
