в четыре часа

at four o'clock

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phrase Rare #42,540
at four o'clock Used to tell the time when something happens. It can mean 4 a.m. or 4 p.m.; add дня for 4 p.m. or утра for 4 a.m. when clarification is needed.
RU: Я позвоню тебе в четыре часа.
EN: I’ll call you at four o’clock.