Using a plural noun as an adjective


New Member
Hello everybody,

I have the following question. I remember from my grammar course that one should say

a 10-year-old child

and I do get that there is no s after year because "10 year old" is considered as an adjective as a whole.

Now I have the following sentence to write (it is about fluid mechanics ;)):
1-The following models belong to the transport models category
2-The following models belong to the transport model category

I want it to mean The following models belong to the category of the transport models but using 1 or 2.

What would the correct form be ? If I'm getting it right, I guess it's the second one but I'm not sure. I'd really appreciate your help :)

Thanks !
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  • Type 2 is always good. In everyday language we almost always use singular. Plural modifier nouns often occur in legal and commercial writing, so probably wouldn't sound wrong in your technical context.
    Naomi Campbell belongs to the runway-models category.
    Naomi Campbell belongs to the runway-model category.

    I like the plural.

    Edit: And there you have it -- a split decision. :) I like the plural by 55 to 45, and I think you can use either correctly.
    entangledbank>thanks for the highlight / context precision
    Copyright>and I like your example ^^

    I will use the plural form then.

    Thanks to the two of you ;)
    The explanation for the lack of -s in the first example (10 years old child) is incorrect. But this is (1) discussed in many other threads already, and (2) has nothing to do with the main question.

    In transport model category, the phrase transport model is a noun, not an adjective. This is a common misunderstanding, relatively unimportant, but it means that we cannot use the argument "Adjectives in English don't take -s" to exclude the plural form right from the start. The fact is that in many situations (even in everyday language), the first noun in a noun-noun compound can and sometimes must be plural.

    In this particular example, without further context, both the singular transport model and the plural transport models sound acceptable to me and express the same meaning.

    Other examples of the same type are discussed in these following threads:
    "Car salesman" but "Events manager" (first noun plural or not)
    Wedding 'Flower/Flowers' Deals [noun as adjective]
    Language(s) - art(s) - student, stamp(s) collecting. Attributive nouns singular/plural.
    procedure or procedures?
    child/children as adjectives
    Why sales representative & human rights situation have s?
    Human rights-groups community
    terrorists blocks
    brands images associations
    school sports club activities or school sport club activities
    a martial arts master
    electronics items
    girl/girls dancers
    pharmaceuticals vs pharmaceutical
    Adjectives and nouns
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    CapnPrep thank you for the additional information.

    But my being wrong with my first explanation does not seem so obvious to me. I know the difference between a noun and an adjective and I said as an adjective ;)

    I read the links you gave me and this article as well and in the end it does not seem so clear to me :p
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    I know the difference between a noun and an adjective and I said as an adjective ;)
    True, but old really is an adjective, so your two examples are totally different from one another. If you want to discuss 10 year old, you might try one of these threads:
    xx years old / xx-year-old
    year / years
    S in four year[s] old

    I read the links you gave me and this article as well and in the end it does not seem so clear to me :p
    Well, I didn't promise you any clear answers… :D This is a part of English grammar that has evolved and is evolving quickly, and so (1) native speakers disagree with each other about many examples, and (2) the rules that people once learned and continue to repeat no longer correspond exactly to current usage.
    I read the three posts and I will stick to:
    Incidentally, the hyphens in forty-year-old are there to indicate that all three words together function as one adjective.

    For noun adjuncts, maybe will I try to investigate further on if I have time :) Thanks anyway!