部(へ)屋(や) heyaに ni忘(わす)れ()物(もの) wasuremonoを oして shiteしまいました shimaimashita。 I accidentally left something behind in the room. Literal Room [in-に] forgotten-item [object-を] did [unfortunately-てしまいました]. 忘れ物をする is the standard expression for leaving something behind. The ~てしまう adds regret for the unintentional forgetting. memorydaily lifesuru-verb (noun + する)~てしまう (regret/completion)
部(へ)屋(や) heyaに ni忘(わす)れ()物(もの) wasuremonoを oして shiteしまいました shimaimashita。 I accidentally left something behind in the room. Literal Room [in-に] forgotten-item [object-を] did [unfortunately-てしまいました]. 忘れ物をする is the standard expression for leaving something behind. The ~てしまう adds regret for the unintentional forgetting. memorydaily lifesuru-verb (noun + する)~てしまう (regret/completion)