彼(かの)女(じょ) kanojoは wa非(ひ)常(じょう)に() hijouniうれしかった ureshikattaので node、踊(おど)り()出(だ)し()た() odoridashita。 She was so happy that she began to dance. Literal She [topic-は] extremely was-happy [so-ので], started-dancing. 踊り出す is a compound verb: 踊る ('to dance') + 出す ('to begin'). The ~出す auxiliary marks the spontaneous onset of an action. ので marks the cause: being so happy. danceemotions~始める (begin to)
彼(かの)女(じょ) kanojoは wa非(ひ)常(じょう)に() hijouniうれしかった ureshikattaので node、踊(おど)り()出(だ)し()た() odoridashita。 She was so happy that she began to dance. Literal She [topic-は] extremely was-happy [so-ので], started-dancing. 踊り出す is a compound verb: 踊る ('to dance') + 出す ('to begin'). The ~出す auxiliary marks the spontaneous onset of an action. ので marks the cause: being so happy. danceemotions~始める (begin to)