[Grammar] Ken’s grandparents chat with their friends on evenings.

[sitifan]

Ken’s grandparents chat with their friends on evenings. (quoted from an English book published by Kangxuan in Taiwan)
Is the expression "on evenings" correct?

 

[GoesStation]

Not in BrE.

Nor in American English.

 

[emsr2d2]

BrE would use "in the evenings" or "of an evening".

 

[Yankee]

BrE would use "in the evenings" or "of an evening".

And occasionally you might hear/read "evenings" without the preposition or article.