# Hyphenation with greek words in xelatex

I am new to latex and I am writing a document in greek. My problem is that If an english word does not fit in the line it breaks, but a greek word does not break and it looks bad. I did a little research and I figured out how to solve the problem partially with this command \hyphenation{απο-τελέσματα}. But this is painful because there are a lot of words that do not break. Is there any way that it detects and breaks the greek words by default? Also its not an issue if it does not break them in a correct way(grammatically) because I will fix them manually with the above command(with the hope that they are fewer than the initial words).

Here is the fonts and packages I use:

\documentclass[runningheads,a4paper]{llncs}

\usepackage{amssymb}
\setcounter{tocdepth}{3}
\usepackage{graphicx}
\usepackage{fontspec}
\usepackage{tikz}
\usepackage{listings}
\usepackage{color}
\setmainfont{DejaVu Serif}

\hyphenation{απο-τελέσματα}
\hyphenation{προγραμματι-σμός}

\lstset{frame=tb,
language=C,
aboveskip=3mm,
belowskip=3mm,
showstringspaces=false,
columns=flexible,
basicstyle={\small\ttfamily},
numbers=none,
numberstyle=\tiny\color{gray},
keywordstyle=\color{blue},
stringstyle=\color{mauve},
breaklines=true,
breakatwhitespace=true,
tabsize=3
}

\begin{document}
.... rest of document ...


Use babel (or polyglossia) and correctly set the language. Then hyphenation will work:

\documentclass[runningheads,a4paper]{llncs}

\usepackage{fontspec}
\usepackage[greek,english]{babel}
\setmainfont{DejaVu Serif}

\textwidth=4mm %for demonstration
\begin{document}
%no hyphenation:
αποτελέσματα
προγραμματισμός

%now it works:
\selectlanguage{greek}
αποτελέσματα
προγραμματισμός
\end{document}


• That worked and it looks great. It was so simple. Thank you a lot for your help ! – Hepic Hepic Aug 14 '18 at 13:55