;; IN: two lists
;; OUT: 1 list, the result of appending the two

;; HINT: recurse down first list
;; EX> (append '(to boldy) '(go))
  (to boldy go)

(define (append ls1 ls2)
   (if (null? ls1) ls2

       (cons (car ls1) (append (cdr ls1) ls2))))