while  (<>) {
        print "$1\n" if /\s*(\w+)\s+NS\s+.*/
       #print what found in parens if the (current) line
       # begins whith zero or more space/tab... one or
       # more letter (we save it by enclosing it in parens)
       # at least one space then the 2 letters NS followed
       # by at least a space anf maybe other char
}