+\documentclass[../thesis.tex]{subfiles}
+
+\begin{document}
+\ifSubfilesClassLoaded{
+ \pagenumbering{arabic}
+}{}
+
+\chapter{Summary}%
+\label{chp:summary}
+\begin{center}
+
+\noindent%
+This is a summary of 350--400 words.
+
+\end{center}
+
+\input{subfilepostamble}
+\end{document}