Update chapters/synchronous.tex

Co-authored-by: Elena Shmoylova <eshmoylova@users.noreply.github.com>

chapters/synchronous.tex

@@ -887,7 +887,7 @@ \subsection{Connected Components of the Equations and Variables Graph}\label{con
 Each use of \lstinline!time! is conceptually included as a separate variable in this analysis, $\mathit{time}_i$ with $\text{\lstinline!der!}(\mathit{time}_{i}) = 1$.
 \begin{nonnormative}
 This means that \lstinline!time! can be used in different partitions without any restrictions.
-Additionally it means that every partition directly referencing \lstinline!time! contains a call to \lstinline!der!.
+Additionally, it means that every partition directly referencing \lstinline!time! contains a call to \lstinline!der!.
 \end{nonnormative}
 
 \subsection{Base-clock Partitioning}\label{base-clock-partitioning}