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diff --git a/exercises/_assignment6.mdwn b/exercises/_assignment6.mdwn
index 0f654f25..ebc20e06 100644
--- a/exercises/_assignment6.mdwn
+++ b/exercises/_assignment6.mdwn
@@ -134,8 +134,9 @@ piece, which we can think of as a function from a type to a type.
 Call this type function M, and let P, Q, R, and S be variables over types.
 
 Recall that a monad requires a singleton function 1:P-> MP, and a
-composition operator >=>: (P->MQ) -> (Q->MR) -> (R->MS) that obey the
-following laws:
+composition operator >=>: (P->MQ) -> (Q->MR) -> (P->MR) [the type for
+the composition operator given here corrects a "type"-o from the class handout]
+that obey the following laws:
 
     1 >=> k = k
     k >=> 1 = k 
@@ -164,3 +165,16 @@ More specifically,
 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 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]) = List.flatten (List.map f (g a))
+
+For example:
+
+     f p = [p, p+1]
+     s q = [q*q, q+q]
+     >=> f s 7 = [49, 14, 64, 16]
+