If you do make or eliminate prefix keys, that changes the set of
possible key sequences. For example, if you redefine @kbd{C-f} as a
prefix, @kbd{C-f C-k} automatically becomes a key (complete, unless you
-define it too as a prefix). Conversely, if you remove the prefix
+define that too as a prefix). Conversely, if you remove the prefix
definition of @kbd{C-x 4}, then @kbd{C-x 4 f} (or @kbd{C-x 4
@var{anything}}) is no longer a key.