"The purple bird sings."
Translation:보라색인 새가 노래합니다.
I suppose "보라색인 새가 노래해요" would be accepted as well. Reported on Nov. 5, 2017.
putting 'the' in every nouns wouldn't be so natural; Korean grammar is very different to european grammar so a natural sentence in Korean might not sound so natural in English, but you must leave it that way. This is because '보라색인 새' could mean a specific bird but it could imply the meaning that 'if a bird is purple, it sings.' The idea of trying to translate Korean phrases in one type of English phrase is misguided, as I say as native Korean myself.