Why is the plural, proper noun 'Mondays' classified as an adverb in the dictionary? I've never heard of a plural, proper adverb.

You will notice that no plurals have their own entry in the dictionary. Look up "dogs", if you do not believe this. Therefore, the plural of the noun Monday would not have its own entry. However, the word Mondays is an adverb of time. It answers the question when.

I hope you see the reasoning.

PLEASE TELL ME THE CORRECT USE OF ( ;).
THANKS IN ADVANCE.

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