The Culmination Of New Information

Halliday & Matthiessen (2014: 116):

The tonic foot defines the culmination of what is New: it marks where the New element ends. In the typical instance, this will be the last functional element of clause structure in the information unit. As this implies, the typical sequence of informational elements is thus Given followed by New. But whereas the end of the New element is marked by tonic prominence, there is nothing to mark where it begins; so there is indeterminacy in the structure. If we take an instance out of context, we can tell that it culminates with the New; but we cannot tell on phonological grounds whether there is a Given element first, or where the boundary between Given and New would be. (This is not always true.)