https://www.englishmirror.com/english-grammar/formation-of-adverbs.html
FORMATION OF ADVERBS
Some original adverbs: seldom, always, yesterday, today, tomorrow, here, there, never, well.Adverbs from adjectives
(a) With the suffix –ly.Examplespossibly humbly thinly gladlysheepishly slowly loudly usuallyslavishly clearly sincerely silently normally finally nicelykindly harshly honestly correctlyrightly beautifully mercifully helpfullywonderfully frequently immediately coldlydully forcefully hatefully painfullysmartly proudly sadly badlymadly fairly hopefully sorrowfullydryly largely wisely fullybravely generally leisurely boldly
(b) By changing the final –y into –(i) and adding –ly.Examplesgaily lazily readily happilyangrily busily merrily hungrilywearily heavily
(c) From adjectives ending in –able, ible, by dropping the final –e and adding –y.Examplesreasonably desirably preferably tolerablyhonorably suitably profitably fashionablyfavorably plausibly forcibly sensibly
(d) Some other adverbs from adjective.ExamplesAdjective Adverbtrue trulydue dulywhole whollyAdverbs from participlesWith the suffix –ly.Examples
A. surprisingly strikingly amazingly increasinglywillingly seemingly knowingly approvinglyhaltingly hesitatingly daringly reassuringlylovingly exceedingly pleasingly displeasinglylongingly imposingly warningly
B. brokenly hurriedly drunkenly admittedlyunexpectedly deservedly doggedly supposedlyfixedly Words same in Adjectives and AdverbsSome words can be used both as Adjectives and Adverbs.ExamplesHigh low near fasthalf deep far hardlate much long leisurelykindly early daily weeklyforthrightly yearly straight hourlynightly only a little enough
