grow by leaps and bounds

Translations
расти не по дням, а по часам
His knowledge of the subject has grown by leaps and bounds over the past few months.
Его знания по этому предмету росли не по дням, а по часам в последние несколько месяцев.
Definitions
To increase or develop very quickly and significantly; to make rapid progress.
Words
grow

verb
расти
by

preposition
на
leaps

noun
скачки
and

conjunction
и
bounds

noun
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