Fix typo in 6.11 Blocks of specs.

Author: liang3zy22

spec/06-expressions.md

@@ -599,7 +599,7 @@ Evaluation of the block entails evaluation of its
 statement sequence, followed by an evaluation of the final expression
 ´e´, which defines the result of the block.
 
-A block expression `{´s_1´; ´\ldots´; ´s_n´; }` where ´s_1 , \ldots , s_n´ are
+A block expression `{´c_1´; ´\ldots´; ´c_n´}` where ´s_1 , \ldots , s_n´ are
 case clauses forms a [pattern matching anonymous function](08-pattern-matching.html#pattern-matching-anonymous-functions).
 
 ###### Example