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diff --git a/assignment4.mdwn b/assignment4.mdwn
index 7ec49f77..74238062 100644
--- a/assignment4.mdwn
+++ b/assignment4.mdwn
@@ -1,12 +1,14 @@
-
 #Reversing a list#
 
-How would you define an operation to reverse a list? (Don't peek at the
+1.	How would you define an operation to reverse a list? (Don't peek at the
 [[lambda_library]]! Try to figure it out on your own.) Choose whichever
 implementation of list you like. Even then, there are various strategies you
 can use.
 
+(See [[hints/Assignment 4 hint 1]] if you need some hints.)
+
 
+#Comparing lists for equality#
 
 <!--
 let list_equal =
@@ -25,11 +27,20 @@ let list_equal =
                 ; (might_for_all_i_know_still_be_equal?, tail_of_reversed_right)
                 ; when left is empty, the lists are equal if right is empty
                 (make_pair
-                    (not (isempty right))
+                    true ; for all we know so far, they might still be equal
                     (reverse right)
                 )
                 ; when fold is finished, check sofar-pair
                 (\might_be_equal right_tail. and might_be_equal (isempty right_tail))
 -->
 
+#Mutually-recursive functions#
+
+
+
+#Enumerating the fringe of a leaf-labeled tree#
+
 [[Implementing trees]]
+
+
+