Debpriya De Why is it so ? Because people have used on in such contexts for ages. If a preposition is used at all, on seems to be used when something other than the plural s is added: in the evening / in the evenings on Tuesday evening, on July evenings, on cold evenings For more examples see CB
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Debpriya DeWhy is it so ?Because people have used on in such contexts for ages. If a preposition is used at all, on seems to be used when something other than the plural s is added: