2.2.3. Intonational phrase
An intonational phrase (IP) has one intonational contour and consists of one or more phonological phrases. Specific intonation patterns are combinations of several non-manual articulators and can sometimes be associated with a specific grammatical function. This is further addressed in PHONOLOGY 2.3.
In general, it has been proposed for sign languages that the non-manual markers accompanying a clause to express a specific grammatical function are domain markers of that specific IP. Generally, at the IP boundary, every non-manual articulator that was involved in marking the (previous) IP changes its features. For instance, when the eyebrows are raised (re) over a topicalized constituent but lowered or neutral over the next constituent, it is likely that we are dealing with two IPs, as in Example 6. Furthermore, in this example, the headshake (hs) signaling negation only accompanies the second IP.
re hs
6. [tomorrow party go]IP / [know not_yet]IP
‘As for whether I’m going to the party tomorrow, I don’t know yet.’
Other boundary markers are head nods and eye blinks, but these are optional and have not been systematically investigated in this context.