Update Sub.pod6

Author: ZzZombo

doc/Type/Sub.pod6

@@ -43,7 +43,7 @@ with complex arguments.
     my $x is foo[1,2,3,:named<a>, :2b, :3c] = 1
     # OUTPUT«[1 [2 3] a {b => 2, c => 3}]␤»
 
-Despite its funky syntax, a trait is just a normal C<Sub>. We an apply traits
+Despite its funky syntax, a trait is just a normal C<Sub>. We can apply traits
 to it (or even themselves) and we can apply traits to objects at runtime.
 
     multi sub trait_mod:<is> (Sub $s, :$foo) is foo {