Fix some documentation typos.

doc/starting.tex

@@ -12,7 +12,7 @@ small set of goals.
 
 Any declaration must occur
 inside a theory, which is in that example called HelloProof and
-labelled with a comment inside double quotes. It contains three goals
+labeled with a comment inside double quotes. It contains three goals
 named $G_1,G_2,G_3$. The first two are basic propositional goals,
 whereas the third involves some integer arithmetic, and thus it
 requires to import the theory of integer arithmetic from the \why
@@ -62,7 +62,7 @@ allows to browse inside the theories.
 %   all} or its shortcut \textsf{Ctrl-E}. This will result is something
 % like the screenshot of Figure~\ref{fig:gui2}.
 In this tree view, we have a structured view of the file: this file
-contains one theory, itself containg three goals.
+contains one theory, itself containing three goals.
 
 
 \begin{figure}[tbp]

doc/syntaxref.tex

@@ -261,13 +261,13 @@ The corresponding rules for computing WP are as follows:
 The other forms of code contracts allow to abstract a piece of code by specifications.
 \begin{itemize}
 \item $\texttt{any}~\{ P \}~\tau~\epsilon~\{ Q \}$ is a
-  non-deterministic expression which requires the precondition $P$ to
-  hold, then makes some side effects $\epsilon$ and returns any value
+  non-deterministic expression that requires the precondition $P$ to
+  hold, then makes some side effects $\epsilon$, and returns any value
   of type $\tau$ such that $Q$ holds. This construct acts as an axiom
-  in the sense that it is not check whether there exists any program
+  in the sense that it does not check whether there exists any program
   that can effectively establish the post-condition (similarly as the
   introduction of a \texttt{val} at the global level).
-\item $\texttt{contract}~e~\{ Q \}$ evaluates expression $e$ and the
+\item $\texttt{contract}~e~\{ Q \}$ evaluates the expression $e$ and
   ensures that the post-condition $Q$ holds afterwards.
 \item $\texttt{abstract}~e~\{ Q \}$ makes sure that the evaluation of
   expression $e$ establishes the post-condition $Q$, and then abstract