Insert "of schemes" in groupoids

Thanks to clarifications
http://stacks.math.columbia.edu/tag/022O#comment-2240

groupoids.tex

@@ -87,18 +87,18 @@ \section{Equivalence relations}
 Let $S$ be a scheme. Let $U$ be a scheme over $S$.
 \begin{enumerate}
 \item A {\it pre-relation} on $U$ over $S$ is any morphism
-$j : R \to U \times_S U$. In this case we set
+of schemes $j : R \to U \times_S U$. In this case we set
 $t = \text{pr}_0 \circ j$ and $s = \text{pr}_1 \circ j$, so
 that $j = (t, s)$.
 \item A {\it relation} on $U$ over $S$ is a monomorphism
-$j : R \to U \times_S U$.
+of schemes $j : R \to U \times_S U$.
 \item A {\it pre-equivalence relation} is a pre-relation
 $j : R \to U \times_S U$ such that the image of
 $j : R(T) \to U(T) \times U(T)$ is an equivalence relation for
 all $T/S$.
-\item We say a morphism $R \to U \times_S U$ is
+\item We say a morphism $R \to U \times_S U$ of schemes is
 an {\it equivalence relation on $U$ over $S$}
-if and only if for every $T/S$ the $T$-valued
+if and only if for every scheme $T$ over $S$ the $T$-valued
 points of $R$ define an equivalence relation
 on the set of $T$-valued points of $U$.
 \end{enumerate}