Question
I live in Tokyo and left my umbrella on the train this morning. I didn’t notice until I walked out of the station into the rain. I want to head to the station office and explain what happened. How do I say “I forgot my umbrella” in Japanese?
Answer by Professional Japanese Teacher
傘（かさ）を忘（わす）れました。
Kasa o wasuremashita.
I forgot my umbrella.
Lost-property in Japan is usually a happy ending — staff are very organized, so you have a good chance of getting your umbrella back. You can walk up to a station attendant and say “Kasa o wasuremashita.” Kasa means “umbrella,” and wasuremashita is the past tense of wasuremasu (to forget).
If you want to add where you left it, say “Densha ni kasa o wasuremashita” (I forgot my umbrella on the train). The attendant will likely ask for the train line and time, then point you to the lost-and-found counter — wasuremono (忘れ物) sentaa — where items from that line are collected.
