(define x 2)

(define (show-x)
  (display x)
  (newline))

(show-x)
(set! x 3)
(show-x)

((lambda ()
   (define x 7)
   (show-x)
   (set! x 8)
   (show-x)))

((lambda ()
   (define (show-x)
     (display x)
     (newline))
   (define x 7)
   (show-x)
   (set! x 8)
   (show-x)))