\version "2.19.65"

\relative c'' {
  \override TextSpanner.bound-details.left.text = "accel."
  \override TextSpanner.bound-details.right.padding = #1
  \acciaccatura e8\startTextSpan d4 d r d
  d2 g4. d8
  e2 r
  R4*4
  r2 r4 \override TextSpanner.bound-details.left.text = "rit." c\stopTextSpan\startTextSpan
  c2. aes4\stopTextSpan
}