According to the structure adverbs can be divided into the following groups:
1. simple adverbs consist only of a word root:
soon, fast, when, well etc.;

2. derived adverbs are formed with suffixes:
-ly (quickly, happily, finally etc.);
-like (warlike, lifelike etc.);
-ward(s) (backwards, forward etc.);
-wise (likewise, clockwise etc.);
3. compound adverbs consist of several word roots:
sometimes, everywhere etc;
4. composite adverbs consist of several words:
at first, as far as, at least etc.