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diff --git a/assignment4.mdwn b/assignment4.mdwn
index 821b92e1..6a528a23 100644
--- a/assignment4.mdwn
+++ b/assignment4.mdwn
@@ -64,19 +64,21 @@ return later in the term to the problem of determining when two trees have the
 same fringe. For now, one straightforward way to determine this would be:
 enumerate the fringe of the first tree. That gives you a list. Enumerate the
 fringe of the second tree. That also gives you a list. Then compare the two
-lists to see if they're equal. (You just programmed this above.)
+lists to see if they're equal. 
 
-Write the fringe-enumeration function. It should work on the implementation of
-trees you designed in the previous step.
+Write the fringe-enumeration function. It should work on the
+implementation of trees you designed in the previous step, and it
+should make use of the list comparison function you wrote for question
+2.  Thus you'll have to make sure you only use Church numerals as the
+labels of your leaves, though nothing enforces this self-discipline.
 
-(See [[hints/Assignment 4 hint 3]] if you need some hints.)
 </OL>
 
 
 
 #Mutually-recursive functions#
 
-<OL start=4>
+<OL start=5>
 <LI>(Challenging.) One way to define the function `even` is to have it hand off
 part of the work to another function `odd`:
 
@@ -134,7 +136,7 @@ definitions of `even` and `odd`?
 notes](/week3/#index4h2) as a model, construct a pair `Y1` and `Y2` that behave
 in the way described.
 
-(See [[hints/Assignment 4 hint 4]] if you need some hints.)
+(See [[hints/Assignment 4 hint 3]] if you need some hints.)
 
 </OL>