And then there's "comely."
The suffix "-ly" is a contraction of "-like", and in proto-Germanic it was used to form adjectives, not adverbs. Modern German still forms adjectives in -lich. So do we actually. In the colloquial speech of some regions, people say, "My dog was lying there, all peaceful-like, and the cat whacked him for no reason."
German in fact does not have many adverbs; it just uses adjectives for the purpose. Adverbs seem to be a recently invented part of speech in the Indo-European languages. We all have a couple of ancient adverbs like "very" and "well." (Although to be truthful "very" is a word we borrowed from the French less than a thousand years ago, along with use, question, second, and a bunch of other really important words you'd expect a language to already have.) But adverbs like quickly, boldly, thoroughly, mainly, importantly, etc... well you can see from the uniform structure that those were all created from adjectives and are not ancient words passed down from the Indo-European tribes.
The Romans did the same thing: they used the suffix -mens to turn Latin adjectives into adverbs. The modern Romance languages still retain that technique; in French it turned into -ment and in Spanish and most of the other languages it became -mente. Rapidamente, solamente, normalmente.
Perhaps one of our Russians can tell us how they form adverbs in Russian?
Chinese of course doesn't even have adjectives. The word we translate as "fast" is really the verb "to be fast." So in order to say "I run fast," they have to say "I run, running is fast."
