strike down (someone) in their prime

Translations
сразить (кого-то) в расцвете сил
The young athlete was struck down in his prime by a sudden illness.
Молодой спортсмен был сражен в расцвете сил внезапной болезнью.
Definitions
To cause the death or downfall of someone when they are at the peak of their health, success, or vitality, often unexpectedly or prematurely.
Words
strike

verb
сразить
down

adverb
вниз
someone

pronoun
кого-то
in

preposition
в
their

article or possessive pronoun
их
prime

noun
расцвет