Parshape not working (and optimization)

Question

I am using the command \parshape inside my document and it doesent seem to work. Any ideas why?

\documentclass[10p, a4paper, twopage]{book}
\usepackage{lipsum}

\begin{document}

\parshape=10 
0.25\hsize 0.5\hsize 
0.24\hsize 0.52\hsize 
0.23\hsize 0.54\hsize 
0.22\hsize 0.56\hsize 
0.21\hsize 0.58\hsize 
0.20\hsize 0.6\hsize 
0.19\hsize 0.62\hsize 
0.18\hsize 0.64\hsize 
0.17\hsize 0.66\hsize 
0.16\hsize 0.68\hsize

\lipsum[1]

\end{document}

It does not throw any errors, the text is just not formatted in any way.

And also, is there a way to optimize all that command writing (parshape parameters)?

Answer 1

The text that should be shaped should immediately follow the \parshape setting:

\documentclass{article}

\usepackage{lipsum}

\begin{document}

\sloppy

\parshape 10 
0.25\hsize 0.5\hsize 
0.24\hsize 0.52\hsize 
0.23\hsize 0.54\hsize 
0.22\hsize 0.56\hsize 
0.21\hsize 0.58\hsize 
0.20\hsize 0.6\hsize 
0.19\hsize 0.62\hsize 
0.18\hsize 0.64\hsize 
0.17\hsize 0.66\hsize 
0.16\hsize 0.68\hsize
\lipsum[1]

\end{document}