I am studying for the CAE and I have some problems with the commas. Example:He forgot about sport for a while but then soeone reminded him that sport exists. (Why no comma between while and but? => Is there a rule?)
Another example: He won the 400 metres, the 100 metres, the long jump, and putting the shot. (Why a comma before and??? Is there a rule?)
I would really aprecciate it to have a rule with the commas..
Thank you very much...