painful is an adjective and can't be pluralised
The countable noun corn (corns) is a word for a spot of thickened skin on the feet that can be painful. There is sometimes more than one corn at a time.The uncountable noun corn (no plural form) is a word for a grain crop. Units of corn are expressed as an ear of corn, a stalk of corn, a bushel of corn, etc.
The word pain is a singular noun. The plural would be pains. "Mark has a pain in his foot." Pain can also be used as a verb. "It pains him to see his wife suffering."
No, painful an adjective, a word that describes a noun (a painful injury, a painful situation).
painful wrist
more painful, most painful
painful!
very painful
It is painful
painful
The positive form is the original adjective. The comparative form shows a greater degree of quality. The superlative form shows the highest degree of quality."Most painful" is the superlative. The positive is "painful", the root adjective. The comparative is "most painful".
That is the correct spelling of "painful."