Answer:

மலை (Malai) vs. மழை (Mazhai):

மலை (Malai) refers to a "mountain" or "hill" in Tamil.

மழை (Mazhai) means "rain" in Tamil.

பணி (Pani) vs. பனி (Pani):

பணி (Pani) typically denotes "work" or "task" in Tamil.

பனி (Pani) can mean "sweat" or "toil" in the context of physical effort.