Translation guide
In Japanese, 'one evening' is typically expressed using a specific time noun like ある晩 or ある夜, depending on the nuance. The choice between 晩 (ban) and 夜 (yoru) can reflect formality or the time frame. Often, the phrase is used in storytelling or to refer to a particular, unspecified evening in the past.
one evening (in a story)
Referring to a particular evening in the past, often in narratives or when recounting an event.
One evening, he suddenly came to visit.
Also means 'one evening/night'. 夜 is more general for 'night' and can feel slightly more casual or modern than 晩. Used interchangeably in many contexts.
One evening, the stars were very beautiful.
Literally 'one night', but can be used in literary or poetic contexts to mean 'one evening'. Often implies the whole night or a special night.
The events of one evening changed his life.
Using 'one evening' as a time adverbial to set the scene for a story or description.
Adding に or のこと after ある晩 makes it a clear time adverbial. ある晩のこと is common in storytelling to mean 'one evening, (something happened)'.
One evening, I heard a strange sound.
Same pattern with 夜. Slightly more casual.
晩 (ban) tends to be used in more formal or literary contexts, while 夜 (yoru) is the everyday word for 'night'. For 'one evening', both are acceptable, but ある晩 is slightly more common in written narratives.
Do not translate 'one evening' as 一つの夕方 (hitotsu no yuugata). This is unnatural. Use ある晩 or ある夜 instead.
One evening, I went to see a movie with a friend.