Update variables.pod6

Hopefully clarify wording (and hyperlink)

Author: jubilatious1

doc/Language/variables.pod6

@@ -19,13 +19,13 @@ associative-sigil C<%> and the callable-sigil C<&>.
 
 Sigils provide a link between syntax, the type system and
 L<containers|/language/containers>. They provide a shortcut for the most
-common type constraints when declaring variables and serve as markers
+common type constraints when declaring variables, and serve as markers
 for L<string interpolation|/language/quoting#Interpolation:_qq>. The
 L<positional-sigil|/language/containers#Flattening,_items_and_containers>
 and the
 L<associative-sigil|/language/containers#Flattening,_items_and_containers>
-provide type constraint that enforce a base type
-L<subscripts|/language/subscripts#Custom_types> require to know what
+provide type constraint that enforce base type
+L<subscripts|/language/subscripts#TOC_Title> required to know what
 methods to dispatch to. The
 L<callable-sigil|/language/containers#Callable_containers> does the same
 for function calls. The latter also tells the compiler where parentheses