Let’s now turn to an interesting case, sentence adverbials, that is, adverbs or adverbial phrases that express the attitude of the speaker towards the main sentence. According to Cruttenden (1997), “most so-called sentence adverbials cannot take the nucleus at all when final in an intonation group”. He gives some examples to prove that point:
(240) *I don’t know how to do it fortunately.
(241) *I’ve found out her telephone number incidentally.
It is quite clear that the accentual pattern above is unacceptable. So, as Cruttenden, Wells and other authors point out, in order for sentence adverbials to be accented they must have their own IPs, usually with a rise tone.
The deaccentuation of final sentence adverbials is, in any case, a very likely possibility, as the following examples show:
(244) The people who didn’t get the spoils  were disproportionately humiliated, I guess (George Saunders; Amarillo, Texas, US).
(249) What’s a minister here for, then? (Paul Eddington; London, UK).