Transcript Empty category phenomena in LFG

Empty category phenomena
in LFG
Nigel Vincent
University of Manchester
Caveat
This presentation was prepared for use at the LFG
Winter School held at the University of
Canterbury, 4-8 July 2004. It was designed to
follow on from the foregoing presentation by
Kersti Börjars. Feel free to make use of it but
please acknowledge the source.
Properties of LFG
• Non-derivational
• Parallel correspondence
• Monotonic
Therefore LFG eschews:
• movement
• the (consequent) use of empty categories
• the (consequent) use of uninterpretable features
(in particular Case and EPP)
Instead, new analytical tools
consistent with LFG
premisses need to be found
A typology of empty categories
Construction
Empty category
Overt category
Finite clause
arguments
pro
pronouns
Non-finite clause,
‘equi’ subjects
Raising/passive
PRO
–
NP/DP trace
anaphors (herself)
Unbounded
dependencies
wh-trace
R expressions
The treatment of ‘pro-drop’
Italian:
canta
(Memo) canta
PRED = ' sing <SUBJ>'
 SUBJ NUM = sg
 SUBJ PERS = 3
 TENSE = present
 SUBJ PRED =

' pro'
f-structure for canta ‘(s)he sings’
PRED


SUBJ



TENSE
' sing < (SUBJ)>
PRED ' pro' 

 
NUM s g  



PERS 3  

pres

English non-pro-drop
English:
sings
Bill sings
vs
*sings
PRED = ' sing  SUBJ'
 SUBJ NUM = sg
 SUBJ PERS = 3
 TENSE = present
Control and raising
• ‘Missing’ subject relatable to matrix verb
• ‘Missing’ subject is a semantic argument of
both verbs = control (aka equi)
e.g. Bill tried to dance
• ‘missing’ subject only a semantic argument
of the infinitival verb = raising
e.g. Bill seemed to dance
equi vs raising
• Equi traditionally handled via a construction
specific empty category with no overt analogue,
viz PRO
Bill tried [PRO to dance]
• Raising handled via movement
[[e] seemed [Bill to dance]
Obligatory (OC) vs nonobligatory (NOC) control
OC antecedents
NOC antecedents
obligatory
optional
local
non-local
c-commanding
not c-commanding
unique
split
Bill tried to dance
•
•
•
•
to dance requires a verb to introduce it
introducing verb is in the next clause up
therefore introducing verb c-commands inf.
no split antecedence, so:
*Bill tried (*for him and Sally) to dance
f-control = OC
‘Let us first observe that Williams’ “obligatory
control” corresponds to our functional control.
That is, the central properties that Williams
takes to be characteristic of obligatory control
follow from our theory of functional control.’
(Bresnan 1982: 350)
Functional control
• Involves ‘structure sharing between SUBJ
of matrix verb and SUBJ of embedded verb
• Structure sharing achieved by means of a
new type of function, namely the ‘open
function’ XCOMP
COMP vs XCOMP
• COMP
Bill said that Sally appointed Sue
COMP
• XCOMP
Bill persuaded
Sally
OBJ
to appoint Sue
XCOMP
Lex entries: say, try, persuade
say
‘say <(SUBJ) (COMP)>’
try
‘try <(SUBJ) (XCOMP)>’
persuade
‘persuade <(SUBJ) (OBJ) (XCOMP)’
Lexical Rule of f-control
For any lexical form:
a) XCOMP SUBJ = OBJ if present
otherwise
b) XCOMP SUBJ = SUBJ
F-structure for try
PRED

TENSE
SUBJ


XCOMP






' Bill'
PRED ' like < (SUBJ ) (OBJ ) >'


SUBJ   




OBJ
'
s
trawberries
'


' try < (SUBJ ) (XCOMP) >'
PRES
try ‘try <(SUBJ), (XCOMP)>’
(XCOMP SUBJ) = (SUBJ)
• ‘exhaustive’: same info referred to in two places in fstructure, so split antecedence impossible
• ‘local’: verb can only subcategorise for a clause
contained in its own immediate constituent
• ‘obligatory’: control pattern can only be introduced
via lexical entry of controlling verb
• ‘c-command’ (or f-command): controlling verb one
clause up and thus subject/object/indirect object
necessarily c-commands controllee
persuade vs promise
‘persuade <(SUBJ), (OBJ), (XCOMP)>’
(XCOMP SUBJ) = (OBJ)
‘promise <(SUBJ), (OBJ), (XCOMP)>’
(XCOMP SUBJ) = (SUBJ)
Lexical form for seem
seem
‘seem < (XCOMP) > (SUBJ)
(XCOMP SUBJ) = (SUBJ)
NB: (SUBJ) outside the angle brackets
shows it is syntactically but not
semantically selected
F-structure for seem
PRED

TENSE
SUBJ


XCOMP






' Bill'
PRED ' like < (SUBJ ) (OBJ ) >'


SUBJ   




OBJ
'
s
trawberries
'


' s eem < (XCOMP) > (SUBJ )'
PRES
believe
‘believe <(SUBJ), (XCOMP)> (OBJ)’
XCOMP SUBJ = OBJ
a-control vs f-control
Functional control
Anaphoric control
(models oblig control)
(models non-oblig control)
Structure sharing
Co-reference
Open functions
Closed functions
Corresponds to PRO
Corresponds to pro
Keep + –ing
i)
Susan discussed visiting Fred (anaphoric)
ii) Susan kept visiting Fred
(functional)
Passive:
• Visiting Fred was discussed/*kept by
Susan
Cleft:
• It was visiting Fred that Susan
discussed/*kept
‘Tough’:
• Visiting Fred is unpleasant for Susan to
discuss/*keep
Gen subj:
• Susan discussed/*kept our visiting Fred
Mechanism of a-control
Add the optional equation
( GF PRED) = ‘pro’
to the lexical entry of a non-finite verb
To visit Fred will annoy Susan
PRED


SUBJ


OBJ

TENSE
' annoy
PRED

SUBJ

OBJ
' Sally '
f ut ure

< (SUBJ) (OBJ)>

' v isit < (SUBJ) (OBJ)>'

' pro'



' Fred'




Obviation:
English want vs Italian volere
• Bill wanted to visit Fred
• Bill wanted Susan to visit Fred
• Memo
voleva
visitare
Federico
Bill
wanted
visit.INF
Fred
• Memo voleva [che Susanna visitasse Federico]
Bill wanted
[that Susan visited Fred]
Wh-movement
• Involves link between a ‘filler’ and a ‘gap’
• What
filler
did Bill put [e] in the box?
gap
Unboundedness vs islands
• Potentially infinite distance between filler
and gap
Who did Bill want Sally to try to invite [e]?
• Yet certain close dependencies are not OK
*What did Bill believe the report Sally said?
(Complex NP Constraint)
Wh-constructions:
the challenge for LFG
•
•
Can we avoid recourse to empty
categories?
The construction seems to refer to
categories/positions not functions:
a) all categories except VP front
b) categories move to a specific cstructure position
DFs vs GFs
A functional account needs to identify a
function for the wh-element:
TOPIC: old information; relatives; topics
FOCUS: new information; questions
SUBJ: grammaticalized DF; default topic
Functional dependencies:
outside-in
Who did Bill visit?
(FOCUS) = (OBJ)
Who did Bill try to visit?
(FOCUS) =
( XCOMP OBJ)
(FOCUS) =
( COMP OBJ)
(FOCUS) =
( COMP XCOMP OBJ)
etc
Who did Bill say that
Susan visited?
Who did Bill say that
Susan tried to visit?
etc
Functional dependencies:
inside-out
Who did Bill visit?
(OBJ) = ( FOCUS)
Who did Bill try to visit?
Who did Bill say that
Susan visited?
(OBJ) =
((XCOMP  FOCUS)
(OBJ) =
((COMP  FOCUS)
Who did Bill say that
Susan tried to visit?
(OBJ) =
((COMP XCOMP  FOCUS)
etc
etc
Functional uncertainty
• The infinite set of possible dependencies
requires a means of selecting the right one
for the sentence in question
• (DF) = ( GF* GF)
(Outside-in)
• (GF) = ((GF* DF) (Inside-out)
Outside-in functional uncertainty
• filler-gap relation expressed solely at fstructure with no empty c-structure
• Island constraints statable as conditions on
the path from filler function to gap function
• ( DF) = ({COMP, XCOMP}* (GF–
COMP))
Off-path constraints
( DF) = ({COMP, XCOMP}* (GF))
• Only COMP and XCOMP can intervene
between filler and gap
• So Complex NP Constraint follows
since NPs cannot be COMPs or
XCOMPs
Inside out functional uncertainty
(IOFU)
• there is an empty node in c-structure
• the empty node is annotated with the equation:
(GF) = ((GF* DF)
• provided there is a legitimate path from the gap to
the required focus or topic function the equations
can be solved and the structure is allowed
Why IOFU?
• f- /c-structure correspondences
• weak crossover effects
• wh- in situ and scope
Canonical structural realization
• SUBJ and OBJ must be realized as nominals
(NP or DP)
(Bresnan 2001)
a) That he would be late, I never would have
believed. (That he would be late = COMP)
b) That he would be late was widely predicted.
(That he would be late = ?)
c) Under the bed, we said they would find him.
(Under the bed = ADJ)
d) Under the bed is where they found him.
(Under the bed = ?)
CSR (cont.)
If that he would be late in (b) is COMP,
and if under the bed in (d) is PP, then CSR
is violated.
So, assume a null expletive subject [e]
Weak Crossover
Who does his mother like [e]? (who ≠ his)
• f-precedence: a piece of f-structure f f-precedes a
piece of f-structure g if the rightmost node
associated with f precedes the rightmost node
associated with g.
• A pronominal P cannot f-precede a constituent on
which P is referentially dependent.