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What do you call the people of Spain? Spains?

Spains took to the streets to celebrate their historic soccer win, clogging [off] (Is off needed) the city.

Please answer the above questions.

Thanks
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Spaniards.

You don't need "off".
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New2grammarWhat do you call the people of Spain? Spains?
Spaniards
New2grammarSpains took to the streets to celebrate their historic soccer win, clogging [off] (Is off needed) the city.
clogging the city is fine.

You could say - clogging up the city.
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Comments  
Thanks, Vorpar.
 Optilang's reply was promoted to an answer.
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