Не совсем то, что нужно, но показывает правильное написание.
Womens и mens это ошибочное написание, которое у носителей в целом нареканий не вызывает. Примерно как у нас "повесить" и "повешать".
Это тем не менее не говорит о том, что такое употребление грамматически верно.
What is the correct way to add a possessive to a plural word that does not end in "s"? Is it women's or womens'?
David Dreaming Bear, Horsethief Canyon, California US
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Women's. Just as "cats' pyjamas" means "pyjamas possessed by cats", so "womens'" would mean possessed by "womens".
Jeremy Marchant, Stroud, Gloucestershire
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It's women's. The apostrophe goes after the s when the plural has an 's', ie "The houses' roofs are covered in snow". Because 'women' is already plural, when you add the possessive 's,' the apostrophe goes before it.
Matthew Redgrave, London
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The former. Women's. Because 'women' is already plural, and is possessive. Ergo, you just add the apostrophe 's'. It would only be womens' if womens without the apostrophe was the plural of woman. Despite the fact "women's" is right, my spellchecker still doesn't like it. I think it makes more mistakes than I do...
Katie Edge, London
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It's women's clothes, children's books, etc.
Anthony McGowan, London, UK
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Women's
Roger Thomson, Brighton
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Women's. The apostrophe for possessives was added by 18th-century grammarians who thought the possessive came from a lost form where it was provided by a separate word rather than a special genitive form (John's hat = John his hat; Johns' hats = Johns their hats). Slightly mad but we're stuck with it. It's women's, children's, men's ...
Keith Mason, London, UK
Это традиционное обозначение отделов в магазинах одежды англоязычных стран. Используется как men's, так и mens.

