Yes it should be hyphenated.
no hyphens - 57 years old is what you are.
Most people would spell it sixteen-year-old child. But over the last 20 years, people are ignoring the hyphens.
Yes, you should use hyphens in "eleven-year-old" when it functions as a compound adjective before a noun. For example, you would say "an eleven-year-old child." However, when using it as a predicate adjective after a verb, you do not need hyphens: "The child is eleven years old."
Yes, there should be hyphens in "thirty-year-old" when used as a compound adjective before a noun. The correct phrasing would be "a thirty-year-old civil war." The hyphens help clarify that "thirty-year-old" is a single descriptor for the civil war.
You hyphenate "35-65 year olds" as "35-65-year-olds." The hyphens connect the numbers to indicate a range and link "year" and "old" to form a compound adjective describing the age group. Always use hyphens in this context to maintain clarity.
It's unneccesary, but you can say 7-year-old boy to make it one word. Just hyphenate any place where you would normally see a space.
Hyphens are used in compound words to clarify meaning or improve readability, such as in "three-year-old." Spaces are sometimes used in compound words to show that they are made up of separate words, such as in "ice cream." The choice between hyphens and spaces depends on style guides and common usage.
like whatever the 11 year old likes
does he like 12 year old girls
No! how is it wrong to like a eighteen year-old??
A person can like a 17 year old. You cannot help who you like.
Yes, "two-year-olds" is hyphenated when used as a compound adjective preceding a noun, such as in "two-year-olds play together." The hyphens help clarify that "two" and "year" modify "olds" collectively. However, when referring to the age alone, you would simply say "two years old."