Defining Xlink

Hi

I have included some xlinks within the text content of an XML document e.g:

<rhyme>The <link xmlns:xlink="http://www.w3c.org/1999/xlink"
xlink:href="cat.gif" xlink:show="new">cat</link> sat on the mat</rhyme>

1.    Presumably <rhyme> and any other elements containing <link> need to be
mixed elements declaring <link> as a child?

2.    Is there any way of declaring <link> just once in the schema so that
it can be used within any elements at random?

3.    Presumably because I have declared the xlink namespace within <link>
in the XML document, I don't have to declare all the xlink attributes in the
schema? Or do I?

Thanks

Charles