alignLyrics =
#(define-music-function
      (parser location alignment text)
      (number? markup?)
    #{
    \once \override LyricText.self-alignment-X = #alignment \lyricmode { #text }
    #})


\relative c'' {
  c8. a16 f4
} \addlyrics {
  le -- \alignLyrics #0.7 bens -- satt
}