From: Philip G. Ratcliffe <philip.ratcliffe@un...>  20061031 09:27:52

> I use amsart class to prepare pages. usually when line is too > crouded I get message like > > Overfull \hbox (9.9368pt too wide) in paragraph > > Then applying hyphenation I can resolve this problem in the most > cases. However when I use math I cannot apply hyphenation. > ... > [snip] Try this code and look at my comments following. \documentclass{amsart} \begin{document} \sloppy We got ambiguity of notation. Writing elements of basis $\star D$\penalty0\hskip0pt\relax vector space $Hom_{D{}^*{}_*}(\mathcal{A},\mathcal{B})$ as ${}_*$\penalty0\hskip0pt\relax rows or ${}^*$\penalty0\hskip0pt\relax rows, we present $\star D$\penalty0\hskip0pt\relax vector space $Hom_{D{}^*{}_*}(\mathcal{A},\mathcal{B})$ as ${}_*{}^* D$\penalty0\hskip0pt\relax\ or ${}^*{}_* D$\penalty0\hskip0pt\relax vector space. \noindent \begin{minipage}{\textwidth} \setlength{\parindent}{\normalparindent} We got ambiguity of notation. Writing elements of basis $\star D$\penalty0\hskip0pt\relax vector space $Hom_{D{}^*{}_*}(\mathcal{A},\mathcal{B})$ as ${}_*$\penalty0\hskip0pt\relax rows or ${}^*$\penalty0\hskip0pt\relax rows, we present $\star D$\penalty0\hskip0pt\relax vector space $Hom_{D{}^*{}_*}(\mathcal{A},\mathcal{B})$ as ${}_*{}^* D$\penalty0\hskip0pt\relax\ or ${}^*{}_* D$\penalty0\hskip0pt\relax vector space. \end{minipage} \end{document} First off, you're not comparing like with like because of the ad hoc \parindent you define  if you look inside amsart.cls you'll see that they use \normalparindent, which gets killed by the minipage environment. The usual (though somewhat sledgehammerish) way to avoid overfull \hbox errors is to use \sloppy or the sloppypar environment (\sloppy is documented in the standard LaTeX2e help file). Robin Fairbairn's "The UK TeX FAQ", available on CTAN, has a very comprehensive section on the problem. Cheers, Phil Ratcliffe 