\documentclass[10pt,a4paper]{report}
\usepackage[Devanagari]{ucharclasses}
	\setTransitionsFor{Devanagari}{\begin{sanskrit}}{\end{sanskrit}}
\usepackage{fontspec}
	\setmainfont{Charis SIL}
	\newfontfamily\sanskritfont[Script=Devanagari]{Sanskrit 2003}
\usepackage{polyglossia}
	\setdefaultlanguage{french}
	\setotherlanguage{sanskrit}

\begin{document}

\section{Phrases types}

भवान्कः। \\
अहं रामः।

\end{document}
