keep on at (someone)

Translations
докучать (кому-то)
He keeps on at his brother to clean the room.
Он докучает своему брату, чтобы тот убрал комнату.
Definitions
To repeatedly ask, nag, or criticize someone about something, often in an annoying or persistent way.
Words
keep

verb
продолжать
on

adverb
дальше
at

preposition
к
someone

pronoun
кто-то