Minor wording improvement to the prerequisites information

git-svn-id: http://svn.linuxfromscratch.org/LFS/trunk/BOOK@6960 4aa44e1e-78dd-0310-a6d2-fbcd4c07a689

prologue/prerequisites.xml

@@ -10,10 +10,10 @@
 <para>Building an LFS system is not a simple task. It requires a certain level
 of existing knowledge of Unix system administration in order to resolve
 problems, and correctly execute the commands listed.  In particular, as an
-absolute minimum, the reader should already have the ability to copy or move
-files and directories, list directory and file contents, and change the current
-directory.  It is also expected that the reader has a reasonable knowledge of
-using and installing Linux software.</para>
+absolute minimum, the reader should already have the ability to use the command
+line (shell) to copy or move files and directories, list directory and file
+contents, and change the current directory.  It is also expected that the reader
+has a reasonable knowledge of using and installing Linux software.</para>
 
 <para>Because the LFS book assumes <emphasis>at least</emphasis> this basic
 level of skill, the various LFS support forums are unlikely to be able to