Parts of Norfolk and Beds may not understand this speech? (5,5)

I believe the answer is:

broad scots

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'not understand this speech?' is the definition.
I know nothing about this answer so I can't tell whether this works.

'parts of norfolk and beds' is the wordplay.
'parts of norfolk' becomes 'broads' (I can't explain this - if you can you should believe this answer much more).
'and' means one lot of letters go next to another.
'beds' becomes 'cots' (cot is a kind of bed).
'broads'+'cots'='BROAD SCOTS'

'may' acts as a link.

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I've seen this clue in The Guardian.

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