"When I was 25yrs old, 25years-old / 25 year-old I entered a university building at night through an open window with the intent of burgling it as I wanted to get myself sent to prison". What is the correct way to insert my age in this sentence please? Thank you in advance
You should always hyphenate something like 25-year-old.
When I turned Twenty five...
Example, She looks like an 18-year-old, you're using that hyphenated phrase with the indefinite article in a pronominal sense. It really means "an 18-year-old girl, so it's like a substitute pronoun.
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