thesyntacticand phonological devicesused toexpress it;theinterfacecomponents encodehow particular grammatical
devicescorrespondtosemanticfocus. Incases such as (52/533)that lacksyntacticeffects, theinterfaceconnectsfocus
only to the prosodic tiers of phonology. On the other hand, if a syntactic structure does have inherent focussing
effects, as in thepseudo-clefts (52/536), wecantreat thisstructureas a constructionalidiomthat servesas an interface
with focus. (The“protosyntactic”principleFocus Last of section 8.7 belongs in this category as well.) As for elliptical
answers such as (52/53C), section 12.2 suggested that they have no further syntactic structure and that they are
interpreted by enriched composition. We can now be slightly more specific: they are taken to be the focus of a
statement whose presupposition is recovered from the preceding question.
Howshouldfocus becodedinconceptual structure?As seenalreadyin(52)and (53),thechoiceoffocusisorthogonal
to argument structure: any argument role can be focussed. Therefore focus does not have a natural home in the
descriptive tier. Is it in the referential tier? No, because nonreferential constituents such as adjective phrases and
predicate nominals can be focussed.
(54) a.It's a BIG star, not a LITTLE star.
b. What Susan is is a PROFESSOR.Following thestandard terminology, letus callthistierinformation structure. Sofar itis fairlytrivial: wecouldseeit justas
an element [Focus] coindexed with a constituent of the descriptive tier in semantics. The interface with phonology
coindexes [Focus] with high stress,^219 and various syntactic constructions in various languages coindex [Focus] with a
particular syntacticconstituent. Therefore, whenwe say, for instance, thatPAT is Focus in (52a), this is short-hand for
saying that this syntactic/phonological constituent is coindexed with [Focus] on the information structure tier.
There seem to be a number of varieties of Focus, supplying slightly different kinds of new information. Various
authors make the distinctions differently, and therefore I will only be suggestive here. The type illustrated in (52) and
(53) is probably the most general. It might be thought of as resolving an uncertainty in the common ground with a
more highly specified entity:Someone went to the party; who was it? It was Pat. Patmay be someone already present in the
discourse, or someone entirely new. I'll call thisordinary focus. In a second type,
410 SEMANTIC AND CONCEPTUAL FOUNDATIONS
(^219) Howdoes high stress end up ontherightword? Ideally, thetransitivityofcoindexationwouldbesufficienttodo thejob. Thedescriptivetier iscoindexedthrough syntaxto
segmentalphonology;nowitisalsocoindexedthroughtheinformationstructuretier tohighstress.Withluck,thiswillbeenough.Buttheproblemistricky(seemanyofthe
sources cited above on the focus-stress interface), so I would be wise here to leave the issue open.