Linguistics II

1
Linguistics II

• Syntax

2
Syntax

• Rules of how words go together to form sentences
• What types of words go together
• How the presence of some words predetermines
  others
• What sequences are legitimate?

3
Word classes

• Classic parts of speech
• closed class (grammatical words)
• Prepositions, articles, pronouns,
• open class (lexical words)
• nouns, verbs, adjectives, adverbs
• How to define word classes
• Form
• Function
• Meaning

4
How to define word classes

• Form (what they look like)
• Distinctive appearance
• morphological behaviour (what inflections can
  they take?)
• Function (what they do)
• What other words do they co-occur with?
• Meaning (what they mean)
• E.g. word which names something, doing word, word
  which describes a quality

5
How to define word classes

• Structuralism substitution classes

The very old man walked slowly down
the street
The very young man walked slowly down the
street
The rather young man walked slowly down the
street
That rather young man walked slowly down the
street
That rather young woman walked slowly down the
street
That rather young woman ran slowly down the
street
That rather young woman ran quickly down the
street
That rather young woman ran quickly up
the street
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How to define word classes

• Structuralism constituents

The very old man walked slowly down
the street
The old man walked slowly
down the street
The man walked slowly
down the street
He walked
slowly down the street
He walked
slowly there
He will walk
slowly there
The very old man walked slowly down
the street
The very old man walked slowly down
the street
7
How to define word classes

• Structuralism constituents

NP
Verb group
AdvP
AdjP
The very old man walked slowly down
the street
The old man walked slowly
down the street
The man walked slowly
down the street
He walked
slowly down the street
He walked
slowly there
He will walk
slowly there
8
Grammar

• Tries to capture the range of possible sentences
  in rules
• Most common type is a context-free grammar
  using a rewrite rule formalism
• (Well explain context-free later)

9
Simple grammar

• S ? NP VP
• S ? NP VP adv
• NP ? det n
• NP ? det AdjG n
• NP ? det n PP
• NP ? det AdjG n PP
• PP ? prep NP

• VP ? v
• VP ? v NP
• VP ? v NP PP
• VP ? v NP
• VP ? v PP
• AdjG ? adj
• AdjG ? adv adj

Lexicon det ? the,this,these,a,an n ?
man,girl,men,girls,apple,street,bowl prep ?
with,to,from,in v ? eat,eats,ate,speak,speaks,s
poke,come,comes,came adj ? big,old,pretty,delici
ous adv ? very,rather,quickly
10
Simple grammar

• Notice that rules always have only one symbol on
  the left-hand side, any number of symbols on the
  right
• Terminal and non-terminal symbols
• Rule could be simplified with some additional
  notation, e.g. brackets to show optionality
• NP ? det (AdjG) n (PP)

11
Tree structures
S
NP
VP
det
n
v
PP
prep
NP
det
n
boy
the
to
spoke
the
girl
12
Tree structures
S
VP
PP
NP
NP
det
n
v
prep
det
n
boy
the
to
spoke
the
girl
13
Simple grammar

• Notice that the rules (despite the direction of
  the arrow) can be used to produce strings
  (starting from a left-hand side) or to verify
  that a given string is grammatical (and to say
  what its structure is)
• What sentences does the grammar account for?
• The grammar generates some strings which we judge
  to be ungrammatical. Why?

14
Subcategorization

• One way to solve overgeneration would be to have
  more specific categories, e.g.
• VP ? vitr
• VP ? vtr NP
• Not so attractive, because it would lead to
  duplication of many rules, and loss of
  generalization
• As a compromise, rules can have additional
  conditions in the form of features

15
Simple grammar with features

• S ? NPnumX VPnumX
• NPnumX ? detnumX nnumX
• NPnumX ? detnumX AdjG nnumX
• VPnumX ? vnumX,typeitr
• VPnumX ? vnumX,typetr NP
• etc

Lexicon detnumsing ? the,this,a,an detnumpl
ur ? the,these nnumsing ?
man,girl,apple,street,bowl nnumplur ?
men,girls vnumsing,typeitr?
eats,ate,speaks,spoke, comes,came vnumplur,typ
eitr ? eat,ate,speak,spoke,come,came vnumsin
g,typetr ? eats,ate vnumplur,typetr ?
eat,ate
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Grammatical functions

• Context-free grammar defines constituency and
  structure
• but says nothing about function
• Sentence-level functions are things like subject,
  object
• Within noun-phrases determiners, modifiers
• In each constituent, one element may be
  identified as the head

17
Complements and adjuncts

• Consider The man smashed the vase with a hammer
  yesterday by accident.
• Complements are arguments closely connected to
  the verb, without which the sentence is
  ungrammatical
• Adjuncts add meaning to the proposition as a
  whole, and are generally optional

18
Complements

• Predictable from (or definitive of) the verbs
  subcategorization frame
• May be compulsory or optional
• Verb specifies its complements in form, function
  and content
• Form NP, PP, that-S, infinitive,
• Function subject, object, prep-obj,
• Content syntactic or semantic features

19
Word order

• Grammar defines word-order
• Globally, languages can be classified according
  to basic word-order
• SVO (verb-medial, eg English)
• SOV (verb-final, eg Hindi, Japanese, German)
• VSO (verb-initial, eg Arabic, Welsh)
• these are the most common
• SVO also means typical NP is det n mod,
  verb-final actually means head-final, etc.

20
Word order

• Some languages have free word-order though few
  are completely free, and choice of word-order
  usually carries pragmatic significance Finnish
  said to be completely free word-order
• Many allow scrambling, eg Japanese, German have
  free word-order as long as verb is final
• Word-order often indicates grammatical function
  (eg English), so free word-order languages must
  compensate, usually with lots of inflectional
  morphology