I've seen the following sentences used. Tell me if both are right.

"He is 30 YEARS old. "
"He is a 30 YEAR old man."
Thanks for that note, learner - I always wondered why there is no -s Emotion: smile
Both are fine.

But you have to write the second one like this:

"He is a 30-year-old man." ("30-year-old" functions as an adjective, so you take the "s" out..)
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 Pemmican's reply was promoted to an answer.
Is it right to say
He is 30 YEAR old.
no.. It is not..

"He is 30 years old" or "He is a 30-year-old man"..
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