Syntactic structure concerns the (apparent) structure of sentences
Syntactic objects are words, groups of words, syntactic categories
such as NOUN and NOUN PHRASE, and syntactic roles such as SUBJECT and
MODIFIER
Semantics (and pragmatics)
Semantic structure concerns the (apparent) structure in the internal
representations for things in the world, as conveyed by language
Semantic objects are (internal representations of) objects
(referents), states
of affairs, events, truth values, discourse entities; semantic roles
such as AGENT, COLOR, and SPEAKER
What about the obvious correspondences?
NOUN and THING
ADJECTIVE and ATTRIBUTE
PAST-TENSE and PAST-TIME
A noun phrase and the thing it refers to
What Syntax Is About
How words (and larger units) go together
Dependency: words are associated by directed, labeled arcs; there
are no constituents
Constituency: words and constituents are grouped into
constituents
A phase-structure grammar specifies the legal groupings
Constituent syntactic roles may or not be labeled (with things
like SUBJECT, HEAD, MODIFIER)
How words (and larger units) are ordered
Examples
Determiners precede their nouns in English noun phrases
Subjects precede their main verbs in English clauses
Tendencies for certain kinds of ordering constraints to co-occur
with others: processing considerations may lead languages to be of one
syntactic type or another
Degree to which constraints apply
Free word-order languages (e.g., Finnish): order of words within a
constituent, constituents within larger constituents may be relatively
unconstrained
Non-configurational languages (e.g., Warlpiri): order of words
within a sentence is relatively unconstrained
What Syntax Is Good For
Word (constituent) order, when it's flexible, is meaningful
(prominence, informativeness: that I like)
Constituents tell us which semantic parts go with which
Syntactic roles (relations) tell us how the semantic parts combine
to form semantic wholes