Strange position of additional lyrics in lilypond

Question

I have a score for a song with two staffs, one for the melody and one for the accompaignment. My staffs are set up like this:

<<
  \new Staff \melodia
  \addlyrics{
  \ritornelloLy
  <<
    \strofaUnoPrimo
    \new Lyrics \strofaUnoSecondo
    \new Lyrics \strofaDuePrimo
    \new Lyrics \strofaDueSecondo
  >>
  }
  \new Staff \accordi
>>

The result looks like this:

Why do those additional lines appear below the second staff?

Answer 1

It is surprising that you obtain any additional lines at all. A proper use of \addlyrics according to its syntax would be putting one or more instances immediately after the voice context containing the melody. You can also use it following a Staff context, in the simple case assuming all voices into that staff have an identical rhythm. So in this case, instead of trying to figure out why your example does not work, I think it is better to show a working example and let you imitate it because the result is probably very similar to what you are trying to achieve.

\new StaffGroup <<
  \new Staff { g'2. }           % melodia
  \addlyrics{ "Lyrics One" }
  \addlyrics{ "Lyrics Two" }
  \addlyrics{ "Lyrics Three" }
  \new Staff { \clef bass \chordmode{ g,2./d } } % accordi
>>