You use hyphens when the words are used before a noun to describe the noun. So yes, hyphens here: * My three-year-old niece likes cats. * The twenty-thousand-dollar prize belonged to his sister. * I have a two-year-old cat and an eleven-year-old cat. But not here: * My niece is three years old and she likes cats. * The prize, which was twenty thousand dollars, belonged to his sister. * I have two cats. One cat is two years old and the other is eleven years old. --------- Also notice: * three-YEAR-old niece * My niece is three YEARS old ---------- English also uses hyphens in certain numbers (20+, 30+, etc.) regardless of where the number occurs in the sentence. So... twenty-one, twenty-two, twenty-three, etc... * My twenty-two-year-old sister is getting married next week. * My sister, who is twenty-two years old, is getting married next week. ------------- Hope that helps!

They need to appear this way in order to use the hyphen (-). They need a noun after them. a 2,000-dollar prize some forty year-old fellows a twenty two year-old guy Have a great day!

Thanks Jerry.

'Fellows' is not really what you want to say. It's dated and a little odd these days. "Friends' or 'everyone" sounds good.