# Capture the first five words including whitespace.
 if ( $text =~ / (\S+ \s+
                  \S+ \s+
                  \S+ \s+
                  \S+ \s+
                  \S+ )/x ) {
     # The regex extracted the first five words
     $text = "$1 ...";

     # Shrink any internal whitespace
     $text =~ s/\s+/ /g;
 }