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diff --git a/assignment8.mdwn b/assignment8.mdwn
index 256b2ce9..f09556f0 100644
--- a/assignment8.mdwn
+++ b/assignment8.mdwn
@@ -45,9 +45,9 @@
 						| Some z' -> Some (move_botleft z')
 					(* return saved label *)
 					in Some current
+				    )
 				| None -> (* we've finished enumerating the fringe *)
 					None
-				)
 			(* return the next_leaf function *)
 			in next_leaf
 			;;
@@ -64,7 +64,7 @@
 			;;
 
 
-2.	Here's another implementation of the same-fringe function, in Scheme. It's taken from <http://c2.com/cgi/wiki?SameFringeProblem>. It uses thunks to delay the evaluation of code that computes the tail of a list of a tree's fringe. It also involves passing continuations (`tailk`s) as arguments. Your assignment is to fill in the blanks in the code, **and also to supply comments to the code,** to explain what every significant piece is doing. Don't forget to supply the comments, this is an important part of the assignment.
+2.	Here's another implementation of the same-fringe function, in Scheme. It's taken from <http://c2.com/cgi/wiki?SameFringeProblem>. It uses thunks to delay the evaluation of code that computes the tail of a list of a tree's fringe. It also involves passing "the rest of the enumeration of the fringe" as a thunk argument (`tail-thunk` below). Your assignment is to fill in the blanks in the code, **and also to supply comments to the code,** to explain what every significant piece is doing. Don't forget to supply the comments, this is an important part of the assignment.
 
 	This code uses Scheme's `cond` construct. That works like this;
 
@@ -109,11 +109,11 @@
 	Here is the implementation:
 
 		(define (lazy-flatten tree)
-		  (letrec ([helper (lambda (tree tailk)
+		  (letrec ([helper (lambda (tree tail-thunk)
 		                  (cond
 		                    [(pair? tree)
-		                      (helper (car tree) (lambda () (helper _____ tailk)))]
-		                    [else (cons tree tailk)]))])
+		                      (helper (car tree) (lambda () (helper _____ tail-thunk)))]
+		                    [else (cons tree tail-thunk)]))])
 		    (helper tree (lambda () _____))))
 		
 		(define (stream-equal? stream1 stream2)