In structures.rakudoc, match semicolon usage to previous example, and reword a sentence (#4701)

* match semicolon usage to previous example

* reword sentence for better clarity

Author: schultzdavid

doc/Language/structures.rakudoc

@@ -44,17 +44,18 @@ internal pointer representation are printed. However
 
     for ^2 {
       my $list = (1, 1);
-      say $list.WHICH
+      say $list.WHICH;
     } # OUTPUT: «List|94674814008432␤List|94674814008432␤»
 
 In this case, C<$list> is using the Scalar sigil and thus will be a L<C<Scalar>|/type/Scalar>. Any scalar with the same value will be exactly the same, as shown when printing the pointers.
 
 =head1 Complex data structures
 
 Complex data structures fall in two different broad categories:
-L<C<Positional>|/type/Positional>, or list-like and
-L<C<Associative>|/type/Associative>, or key-value pair like, according to how you
-access its first-level elements. In general, complex data structures, including
+L<C<Positional>|/type/Positional> or list-like on the one hand, and
+L<C<Associative>|/type/Associative> or key-value pair like on the other hand,
+according to how you access its first-level elements.
+In general, complex data structures, including
 objects, will be a combination of both, with object properties assimilated to
 key-value pairs. While all objects subclass L<C<Mu>|/type/Mu>, in general complex objects
 are instances of subclasses of L<C<Any>|/type/Any>. While it is theoretically possible to mix