its supposed to be 20 year old

They are all correct, the both.

gudvibz:
I think it's when you say "a 20 year old " that's when it's correct not just "20year old"

Another olódo
But you're correct shA

it's 20year old, why? because 20 and year are adjectives adding more meaning to the noun old. one of the rules is no plural for adjectives. that's y we have sth like
3 man panel or 3 man defence, and not 3 men panel or 3 men defence, hope have clarified.
I rest my case.

EmergencyCase:
On point but the second context has to go with a hyphen.

Yes I know, I was typing in a haste

It all depends on contextual usage

A 20 year old thief



The thief is 20 years old



So it depends on how you apply it.



Both are correct when used properly

Our English teacher always beat me because of preposition miss use , where is hi now I will kill him

How can saying it correctly will stop western people calling you black and local English speaker's?

Op, it depends on the usage.
When it's used as a adjectival phrase. 20-year-old is correct. But when it's a verb construct. It becomes '20 years old'.
E.g.
The 20-year-old football star has just been signed by Arsenal football club for a club record fee.

The football star who has just been signed by arsenal football club is 20 years old.


Note: in the first scenario, it's used as an adjective of 'football star'. While in the second scenario, it's used as a verb construct to the verb 'is'.

Mobsync:
Year old is an adjective since it is used to describe, modify, qualify or add more meaning to a noun.

You use year old when the age is describing the noun. So you say, I am a 20-year-old (note the use of "a")

Also, most people including me add hyphens when using year old as an adjective. I don't know whether its compulsory though.


Years old is a noun.

You use it when the age itself is the noun in the sentence. So, you say, I am 20 years old.

One rule of the thumb is that you can always skip the "years old" when it is a noun. So you can say, I am 20 but you cannot say I am a 20 man or I am a 20.


So, check what I've written and compare it with the context in which you used "year old."

This post I quoted should be showered with likes! I mean one can't explain any better. "20 year old girl" is used sometimes when the name of the girl in question is unknown so it qualifies the noun girl.

20 Earth Years

Chikita66:
20years old, you can only say 1year old.

dont mind dem

Let dem argue with dia village ppl

Mobsync:
Year old is an adjective since it is used to describe, modify, qualify or add more meaning to a noun.

You use year old when the age is describing the noun. So you say, I am a 20-year-old or I am a 20-year-old man (note the use of "a")

Also, most people including me add hyphens when using year old as an adjective. I don't know whether its compulsory thoug


Years old is a noun.

You use years old when the age itself is the noun in the sentence. So, you say, I am 20 years old.

Rule of the Thumb: You can always skip the "years old" when the age is the noun. So you can say, I am 20. But you cannot say I am a 20 or I am a 20 man.


So, check what I've written and compare it with the context in which you used "year old."

Linguistic student spotted

If the purpose of communication is to pass information, then both are absolutely correct because we understand the statement.

jonero4:
a 20 year old

20 years old

20 years ago

aged 20yrs

Money you spent in school was fruitful.

ayoblinks:
Guys i was discussing wit somebody and i said 20 year old, he burst into laughter and i asked why he was laughing, then he said its 20 years old nd not d former...i disagreed wit him but can anyone enlighten me more on this please...
Mods pls do the needful

u were President Mohammadu Buhari class mate in the military?

a 20 year old
20 years old
20 years ago
aged 20yrs i concur

Money you spent in school was fruitful. udonmenit

FromZeroToHero:
It depends on the context. The 38 year old footballer (Ronaldinho) played for Barcelona for 5 years before his transfer to A.C Milan

[left][/left][/color][color=#006600] wen old is added to the years, you can not longer pluralise it by adding S alphabet but wen there's no old, u add S. e.g I'm 20 years(correct) I'm 20 years old(wrong)

pls is this english correct am 18 i will soon clock 19

pls what about this. Ten thousand naira or Ten thousands naira

Don't forget your hyphen too. That is A 20-Year old boy
I'm 20 years old

I think when you are reporting or referring you use 'a 20 year old lady', but if it's quite personal you can say 'i am 20 years old'. You can see that that there was 'lady' in the first one to show reference but u don't need it in d second one cos its obvious to the hearer what gender u are or so.
Wo, I don tire, the person under me will explain very well I'm sure.

Jackossky:

I am a 20 year old man.... Correct

dis one weak me

EmergencyCase:
On point but the second context has to go with a hyphen.

Ohhhh Lord all this Engrish teacha demmm


Brother me, abeq which wan is hypen??

chubinwa:

dis one weak me

It shouldn't, this is English Bro.

Mobsync:
Year old is an adjective since it is used to describe, modify, qualify or add more meaning to a noun.

You use year old when the age is describing the noun. So you say, I am a 20-year-old or I am a 20-year-old man (note the use of "a")

Also, most people including me add hyphens when using year old as an adjective. I don't know whether its compulsory though.


Years old is a noun.

You use years old when the age itself is the noun in the sentence. So, you say, I am 20 years old.

Rule of the Thumb: You can always skip the "years old" when the age is the noun. So you can say, I am 20. But you cannot say I am a 20 or I am a 20 man.


So, check what I've written and compare it with the context in which you used "year old."

This appears to be the most correct answer to the question.

On wether the addition of hyphen is compulsory, YES it is. When you say "A" the next object which the "a" describe must be SINGULAR. The hyphens makes it (a 20-year-old) singular.

Nairaland ti take over. Google search go soon de learn .....

coz nairaland got all d answeres

Emeskhalifa:


Ohhhh Lord all this Engrish teacha demmm


Brother me, abeq which wan is hypen??

Lol. This sign '----' which also means minus.

if there is an hyphen it will not take 's' . if there is no, hyphen it will be years