The word Doubtfuly is misspelled against Doubtfully, an adverb meaning "In a doubtful manner."
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Doubtfully has double "ll" is mispronounced as "l"
Remember double 'LL' in between the strings doubtfu & y which should not be misspelled with single 'L'
Wrong Spelling: doubtfu-l-y
Correct Spelling: doubtfu-ll-y
Check more misspelled words of Doubtfully to spell it correct.