Grammar is not a question of something "feeling right" (or should that be "rightly" : smile). You do not feel "sickly" but rather "sick"; you do not feel goodly about something but rather good. You are modifying the subject not the verb -- an adverb is thus incorrect. Many people "feel" that some grammar choices are correctly (smile) and are feeling completely wrongly -- English is being machine gunned by this sort of approach a zillion times a day by people over-correcting into illiterate speech.
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