at the age of
prep. phr..prep. phr.. You use this phrase to say how old someone was when something happened in their life.
prep. phr.. A prepositional phrase that specifies the exact age of a person when a particular event took place.
She learned to swim at the age of five.
He moved to Canada at the age of 25 to start a new job.
The prodigy composed her first symphony at the age of twelve, an astonishing feat that captivated the musical world.
This phrase is always followed by a number indicating the person's age.
Contrast with the more conversational 'when [subject] was [age]', noting that 'at the age of' is slightly more formal and common in writing.
He started university in age of 18.He started university at the age of 18.The correct prepositions are 'at' and 'of', and the article 'the' is required before 'age'.