A little help please.
How do you say ... they(cantos) must sound poetic and the singer must sing along with a guitar.
2 Answers
There are a few things you could say if the people singing are not also the people playing the guitar.
The singer's words must be inspiring and they must be in harmony with the guitarist's melody.
The vocals must be inspiring and match the guitarist's playing.
Or,
The vocals must be inspiring and keep pace with the guitarist.
"The vocals" in this case doesn't mean "the singers" but instead the sounds that come out of the singers, whether it is words or gibberish.
Do you mean a poetic word for 'song'? Perhaps melody?