I've always been taught that the word 'staff' (as in employees of a company) is plural, so there is no such word as 'staffs'.
Just today, however, while editing a draft article, I came across the word 'staffs' being used in a sentence:
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Congratulations to the following staff who have passed all 3 modules of the certification course successfully:
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Making a research on the web to confirm the invalidity of the word 'staffs' I discover two contradicting versions of advice from two different English Expert sites.
1)
English plural - Wikipedia, the free encyclopedia
Note 2: For staff in the sense of "a body of employees", the plural is always staffs; otherwise, both staffs and staves are acceptable, except in compounds; such as flagstaffs. The stave of a barrel or cask is a back-formation from staves, which is its plural. (See the Plural to singular by back-formation section below.)
2)
General Writing and Grammar Help: Is "staff" plural/subject verb agreement
Collective nouns are always tough, and it usually depends on how you intend to use the word "staff." If you mean the staff AS A UNIT, then use the singular verb form (provides). If you mean every member of the staff, use "provide."
Please advise which is correct?