English for Today by Ganiu Abisoye Bamgbose (Dr GAB)
PLURALISING COMPOUND NOUNS
I was helped by some ~passerbys~ (nonstandard).
I was helped by some *passersby* (standard).
You have to honour your ~parent-in-laws~ (nonstandard).
You have to honour your *parents-in-law* (standard).
This also applies to “fathers-in-law” and “mothers-in-law”.
I know some ~notary publics~ (nonstandard).
I know some *notaries public* (standard).
A notary public is a public official, usually a solicitor, who is legally authorised to administer oaths, attest and certify certain documents, etc.
GAB
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