[TxMt] refining scopes

In the bundle I've created I'm attempting to refine my scopes. Take the following example:

INT. SHIPYARD DOCKS - DAY

The above line falls under the scopes "text.splay.screenplay" (the document) and "splay.slugline" (the element). What I want is to be able to define the three separate elements: "INT", "SHIPYARD DOCKS", "DAY" as independent scopes, while retaining their status as "splay.slugline" So "INT" would fall under the jurisdiction of "text.splay.screenplay splay.slugline splay.slugline.setting".

I guess the simple question is: how do you stack more than two (the document and the element) scopes?

In Markdown a link gets text.html.markdown, markup.paragraph.markdown, markup.underline.link.markdown... how do I do that?