kurz – lange
dick – dünn
dumm – klug, schlau, intelligent
gut – schlecht
angenehm – unangenehm
sympathisch – unsympathisch
faire – unfair
-ig ending is pronounced “-ich”
richtig – richtich
wichtig – wichtich
König – Könich
Sp- and St- at the beginning of a word or syllable is pronounced “Schp…” “Scht…”:
Schtraße, Schprache, schprechen
the en- ending of a word or syllable is pronounced “-n”:
the er-ending is pronounced with a very weak “a”
Butter – Butta
The English adverbs – most of them – have an ly-tag: beautifully, thoroughly, hastily.
There are German words ending on -lich. But even they are not adverbs!
The difference between German adjectives and adverbs is Zero: “Die Maschine ist laut” vs “Sie singt laut”.