Minor rewording

[ci skip]

base/lthooks.dtx

@@ -335,8 +335,9 @@
 %    or if the \meta{hook} does not exist, a warning is issued when
 %    you attempt to \cs{RemoveFromHook}, and the command is ignored.
 %    \cs{RemoveFromHook} should be used when you know exactly what
-%    labels are in a hook, usually added and removed within the same
-%    package.  If you want to prevent the execution of code from another
+%    labels are in a hook, usually some code is added to a hook, and
+%    later removed by that same package
+%    If you want to prevent the execution of code from another
 %    package, use the |voids| rule instead (see section~\ref{sec:rules}).
 %
 %    If the optional \meta{label} argument is \texttt{*}, then all code chunks are