When you write a text, or speak carefully, and want the sentences to "flow" from one to another, you frequently use fancy words to start them, like "however", "furthermore", "nevertheless". Such "fancy start words" are sometimes called conjunctive adverbs or connectors.
They indicate a relation of the sentence they start with stuff already said, e.g. consequence, completion, opposition, etc. Here are main connectors with English counterparts:
relation English Croatian consequence "therefore" dakle,
"on the contrary" naprotiv,
expected "of course",
"nevertheless" usprkos tome,
opposition "however" međutim,
emphasis "in fact" zapravo similarity "likewise" slično,
conclusion "finally" konačno,
change of subject ? nego
(in coll. speech)
All such "starts" are usually separated by a comma (,) from the rest of the sentence. Some examples:
Naravno, pit ćemo pivo. "Of course, we will drink beer."