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diff --git a/exercises/_assignment6.mdwn b/exercises/_assignment6.mdwn
index cd9db086..ebc20e06 100644
--- a/exercises/_assignment6.mdwn
+++ b/exercises/_assignment6.mdwn
@@ -166,23 +166,15 @@ Then the obvious singleton for the Option monad is \p.Just p.  Give
 (or reconstruct) the composition operator >=> we discussed in class.
 Show your composition operator obeys the monad laws.
 
-2. Do the same with crossy lists.  That is, given an arbitrary type
-'a, let the boxed type be a list of objects of type 'a.  The singleton
+2. Do the same with lists.  That is, given an arbitrary type
+'a, let the boxed type be ['a], i.e., a list of objects of type 'a.  The singleton
 is `\p.[p]`, and the composition operator is 
 
-       >=> (first:P->[Q]) (second:Q->[R]) :(P->[R]) = fun p -> [r | q <- first p, r <- second q]
+       >=> (first:P->[Q]) (second:Q->[R]) :(P->[R]) = List.flatten (List.map f (g a))
 
-Sanity check: 
+For example:
 
      f p = [p, p+1]
      s q = [q*q, q+q]
      >=> f s 7 = [49, 14, 64, 16]
 
-3. Do the same for zippy lists.  That is, you need to find a
-composition operator such that
-
-      f p = [p, p+1]
-      s q = [q*q, q+q]
-      >=> f s 7 = [49, 64]
-
-and then prove it obeys the monad laws.