Lyrics with repeats

[Carl-Peter Krause]

Hello,

I like to create a sheet with a song beginning with the refrain and two verses 
having a repeat block. To position to the 2nd line of the repeat I am adding 
underscore characters (see below). This results in reserving space for a 
whole text line even in the refrain. How can I suppress this extra space?

melody = ...

textA = \lyricmode {
        text of refrain
        1st verse: 1st line of repeat
}

textB = \lyricmode {
        _ _ _ _ _
        1st verse: 2nd line of repeat
}

textC = \lyricmode {
        text of refrain
        2nd verse: 1st line of repeat
}

textB = \lyricmode {
        _ _ _ _ _
        2nd verse: 2nd line of repeat
}

\score {
        <<
                \context Voice = one {
                        \melody
                }
                \lyricsto "one" \new Lyrics \textA
                \lyricsto "one" \new Lyrics \textB
                \lyricsto "one" \new Lyrics \textC
                \lyricsto "one" \new Lyrics \textD
        >>
        \layout {
                linewidth = 18\cm
                textheight = 25\cm
        }
}

Kind regards
Carl-Peter Krause