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diff --git a/assignment3.mdwn b/assignment3.mdwn
index 9f64d808..9039a957 100644
--- a/assignment3.mdwn
+++ b/assignment3.mdwn
@@ -6,7 +6,8 @@ assignment much faster and more secure.
 
 *Writing recursive functions on version 1 style lists*
 
-Recall that version 1 style lists are constructed like this:
+Recall that version 1 style lists are constructed like this (see
+[[lists and numbers]]):
 
 <pre>
 ; booleans
@@ -35,12 +36,11 @@ let isZero = \n. n (\x. false) true in
 let succ = \n s z. s (n s z) in
 let mult = \m n s. m (n s) in
 let length = Y (\length l. isNil l 0 (succ (length (tail l)))) in
-let predecessor = \n. length (tail (n (\p. makeList meh p) nil)) in
-let leq = ; (leq m n) will be true iff m is less than or equal to n
-  Y (\leq m n. isZero m true (isZero n false (leq (predecessor m)(predecessor n)))) in
+let pred = \n. isZero n 0 (length (tail (n (\p. makeList meh p) nil))) in
+let leq = \m n. isZero(n pred m) in
 let eq = \m n. and (leq m n)(leq n m) in
 
-eq 3 3
+eq 2 2 yes no
 </pre>
 
 
@@ -106,14 +106,16 @@ be your base case for your recursive functions that operate on trees.
 Write a function that sums the number of leaves in a tree.
 Expected behavior:
 
-let t1 = (make-list 1 nil) 
-let t2 = (make-list 2 nil)
-let t3 = (make-list 3 nil)
-let t12 = (make-list t1 (make-list t2 nil))
-let t23 = (make-list t2 (make-list t3 nil))
-let ta = (make-list t1 t23)
-let tb = (make-list t12 t3)
-let tc = (make-list t1 (make-list t23 nil))
+<pre>
+
+let t1 = (make-list 1 nil) in
+let t2 = (make-list 2 nil) in
+let t3 = (make-list 3 nil) in
+let t12 = (make-list t1 (make-list t2 nil)) in
+let t23 = (make-list t2 (make-list t3 nil)) in
+let ta = (make-list t1 t23) in
+let tb = (make-list t12 t3) in
+let tc = (make-list t1 (make-list t23 nil)) in
 
 count-leaves t1 ~~> 1
 count-leaves t2 ~~> 2
@@ -123,6 +125,7 @@ count-leaves t23 ~~> 5
 count-leaves ta ~~> 6
 count-leaves tb ~~> 6
 count-leaves tc ~~> 6
+<pre>
 
 Write a function that counts the number of leaves.
 
@@ -147,3 +150,12 @@ reverse (makeList 1 (makeList 2 (makeList 3 nil)))
 It may require more resources than my browser is willing to devote to
 JavaScript.]
 
+; trees
+let t1 = (makeList 1 nil) in
+let t2 = (makeList 2 nil) in
+let t3 = (makeList 3 nil) in
+let t12 = (makeList t1 (makeList t2 nil)) in
+let t23 = (makeList t2 (makeList t3 nil)) in
+let ta = (makeList t1 t23) in
+let tb = (makeList t12 t3) in
+let tc = (makeList t1 (makeList t23 nil)) in