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diff --git a/exercises/assignment8-9.mdwn b/exercises/assignment8-9.mdwn
index 8eb4bc7a..fbdeb850 100644
--- a/exercises/assignment8-9.mdwn
+++ b/exercises/assignment8-9.mdwn
@@ -14,26 +14,27 @@ relationships, as in
 
         John_x thinks Mary_y said he_x likes her_y.
 
-    See her 1999 paper for details.
+    See her 1999 paper for details. Essentially, she ends up layering several
+Reader monads over each other.
 
     Here is [[code for the arithmetic tree Chris presented in week 8|code/arith1.ml]]. It computes
-`\x. (+ 1 (* (/ 6 x) 4))`.  Your task is to modify it to compute
-`\x y. (+ 1 (* (/ 6 x) y))`.  You will need to modify five lines.
+`\n. (+ 1 (* (/ 6 n) 4))`.  Your task is to modify it to compute
+`\n m. (+ 1 (* (/ 6 n) m))`.  You will need to modify five lines.
 The first one is the type of a boxed int.  Instead of `type num = int
 -> int`, you'll need
 
         type num = int -> int -> int
 
     The second and third are the definitions of `mid` and `map2`. The fourth
-is the one that encodes the variable `x`, the line that begins `(Leaf
-(Num (fun x -> ...`.  The fifth line you need to modify is the one
-that replaces "4" with "y".  When you have these lines modified,
+is the one that encodes the variable `n`, the line that begins `(Leaf
+(Num (fun n -> ...`.  The fifth line you need to modify is the one
+that replaces "4" with "m".  When you have these lines modified,
 you should be able to execute the following expression:
 
         # match eval t2 with Leaf (Num f) -> f 2 4;;
         - : int = 13
 
-2. Based on the evaluator code from the assignment from week 7, and what you've learned about the Reader monad,
+2. Based on [[the evaluator code from assignment 7|/exercises/assignment7/#index3h2]], and what you've learned about the Reader monad,
 enhance the arithmetic tree code to handle an arbitrary set of free variables. Don't use Juli8 libraries for this; just do it by hand.
 Return to the original code (that is, before the modifications required by the previous problem).