Add suggested 'The' at start of sentence

Co-authored-by: Hans Olsson <HansOlsson@users.noreply.github.com>

chapters/statements.tex

@@ -343,7 +343,7 @@ \subsection{Return-Statements}\label{return-statements}
 
 \subsection{If-Statement}\label{if-statement}
 
-\lstinline!if!-statements\index{if@\robustinline{if}!statement}\index{then@\robustinline{then}!if-statement@\robustinline{if}-statement}\index{else@\robustinline{else}!if-statement@\robustinline{if}-statement}\index{elseif@\robustinline{elseif}!if-statement@\robustinline{if}-statement} have the following syntax:
+The \lstinline!if!-statements\index{if@\robustinline{if}!statement}\index{then@\robustinline{then}!if-statement@\robustinline{if}-statement}\index{else@\robustinline{else}!if-statement@\robustinline{if}-statement}\index{elseif@\robustinline{elseif}!if-statement@\robustinline{if}-statement} have the following syntax:
 \begin{lstlisting}[language=grammar]
 if expression then
   { statement ";" }