fix two typos, one I created on my last commit

doc/Language/typesystem.pod6

@@ -392,7 +392,7 @@ Enumerations provide constant key-value-pairs with an associated type. Any key
 is of that type and injected as a symbol into the current scope. If the symbol
 is used, it is treated as a constant expression and the symbol is replaced with
 the value of the enum-pair. Any Enumeration inherits methods from the role
-C<Enumeration>. Complex expressions for generating key-value-pairs are
+C<Enumeration>. Complex expressions for generating key-value pairs are
 not supported.
 
 Stringification of the symbol will provide the key of the enum-pair.
@@ -441,7 +441,7 @@ introspectiveness. The returned object is of type C<Map>.
     say $e.WHAT; # OUTPUT«(Map)␤»
 
 There are various methods to get access to keys and values. All of them turn the
-values into C<Str>, which may not be desireable. By treating the enum as a
+values into C<Str>, which may not be desirable. By treating the enum as a
 package, we can get a list of type objects for the keys.
 
     enum E(<one two>); dd E::.values;