How can these be associated with document markup?
One approach is to extend HTML
Another would be to add behavior via a style sheet, e.g.
a.confirm:before { content: "To" }
a.confirm:after { content: "say yes or press" counter(key) }
a.confirm {
timeout: 2s;
speech-grammar: "yes"|"sure"|"ok";
}
...
<a class="confirm" href="message.html">Leave us a message</a>