(case (* 2 3)
  ((2 3 5 7) 'prime)
  ((1 4 6 8 9) 'composite))
(case (car '(c d))
  ((a) 'a)
  ((b) 'b))
(case (car '(c d))
  ((a e i o u) 'vowel)
  ((w y) 'semivowel)
  (else 'consonant))
(case 'a
  ((b c) (display "not reached") (newline) 'b)
  ((a d) (display "reached") (newline) 'a))