"abunai（危ない）"is an adjective. It means "dangerous." "abunaku（危なく）" is another form of "abunai," which is used in various grammatical structures, though "abunaku" itself doesn't make sense as a sentence. For example, "abunaku-nai" means "not dangerous." "abunaku-naru" means "become dangerous." "abunaku-te" means "because it's dangerous"

hey...can iask u..whts ur profession? how many languages ur studying?is not good..i think u must learn one language first thn go to other language...baki tumari wish..

"abunai " is an adjective, which means dangerous. "abunaku" is also an ajective but used as an adverb. This means " nearly , almost". ( see also "ayauku") for example, I was nearly run over by a car----- Abunaku kurumani hikareru tokoro deshita.