Transcript lex-smx - School of Computer Science

Overview of Lexical Semantics
of Verbs
Lori Levin
December 1, 2003
What is Lexical Semantics?
• Lexical semantics is about the meanings of words.
• It is not about sentence-level meaning:
– Truth conditions of sentences
– How meanings noun phrases and verb phrases are
combined compositionally to make meanings of
sentences
– Quantifier scope
– Etc.
Aspects of lexical semantics not
covered in this lecture
• Nouns, adjectives, adverbs, and prepositions
• Selectional restrictions:
– Colorless green ideas sleep furiously
• Count and mass nouns:
– There was water all over the driveway.
– There was dog all over the driveway.
Outline
• Transitivity alternations and semantic
classes of verbs
• Lexical aspect
• Lexical conflation
• How universal is lexical semantics?
• Unaccusative verbs (non-agentive subjects)
• Survey of computational lexicon projects
Transitivity Alternations
• Transitivity – does the verb have a direct
object or not.
• Transitivity alternations:
– Broader meaning
– Changes in the number of arguments a verb has
– Changes in the grammatical relations of
arguments
English Transitivity Alternations
• Beth Levin, 1993
– Identified around 100 transitivity alternations in
English.
Transitivity Alternations and
Semantic Classes: Examples
• Causative-Inchoative: change of state verbs
–
–
–
–
–
–
Sam broke the glass. (causative)
The glass broke.
(inchoative)
Sam opened the door.
The door opened.
Sam kicked the ball.
*The ball kicked.
• In other languages
– Inchoative verbs may be reflexive (e.g., Romance languages)
– There may be a causative marker on the transitive verb.
• Inchoative means beginning.
– Beginning a change of state?
Transitivity Alternations and
Semantic Classes: Examples
• Dative Shift: giving and telling
–
–
–
–
–
–
I gave Sam the book.
I gave the book to Sam.
I told the story to the children.
I told the children the story.
I drove the car to New York.
*I drove New York the car.
• In other languages
– The goal may not be able to become a direct object.
(Romance languages)
– The goal may become a direct object in the presence of
an applicative morpheme. (Bantu languages)
Transitivity Alternations and
Semantic Classes: Examples
• Spray-Load Alternation: filling and
covering.
–
–
–
–
Sam sprayed the wall with paint.
Sam sprayed paint on the wall.
Sam loaded the truck with hay.
Sam loaded hay onto the truck.
Transitivity Alternations and
Semantic Classes: Examples
• There Insertion: stative, appearing
–
–
–
–
–
–
–
–
Problems exist.
There exist problems.
A ghost appeared.
There appeared a ghost.
The students worked.
*There worked some students.
The students disappeared.
*There disappeared some students.
Transitivity Alternations and
Semantic Classes: Examples
• Locative subjects:
– Bees swarmed in the garden.
– The garden swarmed with bees.
• Temporal subjects:
– 1990 saw the fall of the government.
Transitivity Alternations and
Semantic Classes: Examples
• Middle: Telic verbs? (see below)
–
–
–
–
–
–
You can cut this bread.
This bread cuts easily.
You can sell these books easily.
These books sell well.
People like these books.
*These books like well.
Transitivity Alternations and
Semantic Classes: Examples
• Resultative Secondary Predication: theme
version
–
–
–
–
Sam hammered the nail.
Sam hammered the nail flat.
The lake froze.
The lake froze solid.
Transitivity Alternations and
Semantic Classes: Examples
• Resultative Secondary Predication: agent
version
– He screamed himself hoarse.
– He cried himself to sleep.
Class shifts
• Manner of motion to change of location:
–
–
–
–
The bottle floated.
The bottle floated into the cave.
The ball bounced.
The ball bounced across the room.
• Sound to change of location:
–
–
–
–
The car rumbled.
The car rumbled down the street.
The dress rustled.
She rustled across the room.
How universal?
• How universal is argument structure?
– If an English word has an agent and a patient, will
the translation-equivalent in another language
have an agent and patient?
– If an English word has a subject and object, will
the translation-equivalent in another language
have a subject and object?
• Less likely:
– I met him.
– I met with him.
How Universal?
• How universal are alternations and semantic
classes?
– If an English word undergoes a transitivity
alternation, will the translation equivalent in
another language undergo the same transitivity
alternation?
• Even less likely. (Mitamura, 1989)
Importance of Transitivity Alternations
in Language Technologies
• For any task that requires understanding
(question answering, information extraction,
machine translation) you need to know the
semantic roles of the NPs.
– The glass broke. (subject is patient)
– The kids ate. (subject is agent)
– I gave them some books (object is recipient)
Importance of Transitivity Alternations
in Language Technologies
• So you need multiple lexical mappings for each
verb:
break < agent patient>
subj obj
break < patient >
subj
give < agent theme recipient>
subj obj obl
give < agent theme recipient>
subj obj2 obj
Importance of Transitivity Alternations
in Language Technologies
• To speed up lexicon acquisition, assigning a verb
to a semantic class and automatically generating
its alternations is faster than listing all of its lexical
mappings by hand.
–
–
–
–
–
–
I gave books to the students.
I gave the students books.
Books were given to the students.
The students were given books.
There were books given to the students.
There were students given books.
Lexical Aspect
• State
– The clock sat on the shelf.
• Activity
– The children painted.
• Accomplishment
– The children walked to school.
• Achievement
– The ambassador arrived in Moscow.
Lexical Aspect
• Took examples from this web page:
http://www.sfu.ca/person/dearmond/322/322.event
.class.htm
• Vendler, Linguistics in Philosophy, 1967
• Dowty, Word Meaning and Montague Grammar,
1979
• Tenny, Aspectual Roles and the Syntax-Semantics
Interface, 1994
Activities and Accomplishments
•
Activity:
– The children painted for an hour.
– ?The children painted in an hour.
– The children will paint in an hour.
• They will start in an hour.
– The children almost painted.
• Almost started painting
– Test for telicity:
• If you start to paint and stop,
you have painted.
• Fails test for telicity.
•
Accomplishment:
– ?The children walked to school for
an hour.
– The children walked to school in
an hour.
– The children will walk to school in
an hour.
• They will start in an hour, or
it will take an hour.
– The children almost walked to
school.
• Almost started walking, or
almost reached school
– Test for telicity:
• If you start to walk to school
and stop, you may not have
walked to school.
• Passes test for telicity.
Telicity
• Telic: has a goal or endpoint
(accomplishment)
• Atelic: does not have a goal or endpoint
(activity)
• Telicity can change depending on the
sentence:
– He built houses for a year/*in a year.
– He built a house in a year/?for a year.
Achievements
• The ambassador almost arrived in Moscow.
– Only means “almost finished” not “almost
started.”
States (English)
• Stative: Simple present tense means present time.
Present progressive does not sound good.
– He knows the answer.
– He is knowing the answer.
• Non-stative: Simple present tense means habitual
or generic. Present progressive means present
time.
– He paints.
– He is painting.
Consequences of Lexical Aspect for
Language Technologies
• English
– You have to know the lexical aspect of the verb in order
to know what the tense morphemes mean.
• The simple present tense means “habitual” with a non-stative
verb, but means present time with a stative verb.
– You have to know the lexical aspect of the verb in order
to know what the adverbials mean.
• Almost can mean “almost started,” “almost finished,” or both.
Consequences of Telicity
– Japanese:
• Telic verbs with –te iru have a resultative
meaning
– Aite iru: is open or has been opened, not is
opening
– Otite iru: is dropped (is on the floor), not is
dropping (unless it takes a very long time to fall,
like a leaf falling off of a sky scraper)
• Atelic verbs with –te iru have a progressive
meaning
– Tabete iru: is eating, not has eaten
Consequences of Telicity
• Japanese: -te aru (with passive-like
meaning) only applies to telic verbs because
it focuses on a resulting state. (e.g., wash
(arau), but not praise (homeru))
Sara ga aratte aru.
Plate subj wash
???Taroo ga homete aru.
Consequences of Telicity: Finnish
• Angelica Kratzer, Telicity and the Meaning of Objective
Case, International Round Table ‘The Syntax and
Semantics of Aspect’, Universite de Paris, Nov. 2000.
• Telic: direct object can have partitive or accusative
case (with a slight difference in meaning):
Ammu-i-n
karhu-a
Shoot-past-1sg bear-part
I shot at a/the bear
Ammu-i-n
karhu-n
Shoot-past-1sg bear-acc
I shot the bear
• Atelic: can only have partitive case: despise,
admire, envy, love, study, play, listen, pull
Consequences of Telicity: Chinese
• Lisa Lai Shen Cheng, Aspects of the Ba-Construction,
Lexicon Project Working Papers 24, Carol Tenny (ed.),
MIT, 1988.
Ta ba shu mai le.
He BA book sell ASP
He sold the book
• Factors determining grammaticality of the ba-construction:
– Aspect markers: occurs with le and zhe, but not with zai and guo.
– Definiteness: The direct object has to be interpretable as definite.
– Telicity of the verb: tui le (pushed) vs. tui dao le (pushed down;
push-fall); la le (pull) vs. la dao le (pull down; pull-fall); dai le
(bring/carry) vs. dai lai le (bring here; carry-come)
“Ba” and Telicity
*Wǒ bǎ Lǐsì tūi-le.
I BA Lisi push-ASP
“I pushed Lisi.”
Wǒ bǎ Lǐsì tūi-dǎo-le.
I BA Lisi push-fall ASP
“I pushed Lisi and he fell.”
“Ba” and Telicity
*Tā bǎ Zhāngsān lā-le.
He BA Zhangsan pull-ASP
“He pulled Zhangsan.”
Tā bǎ Zhāngsān lā-dǎo-le.
He BA Zhangsan pull-fall-ASP
“He pulled Zhangsan and Zhangsan fell.”
“Ba” and Telicity
*Tā
bǎ dìan-nǎo dài-le.
He BA computer bring-ASP
“He brought the computer.”
(Does this really mean “He carried the computer?”)
Tā bǎ dìan-nǎo dài-lái-le.
He BA computer bring-come-ASP
“He brought the computer here.”
“Ba” and Telicity
bǎ fángjīan dǎ-sǎo-le.
He BA room hit-sweep-ASP
“He cleaned the room.”
*Tā
Tā bǎ fángjīan dǎ-sǎo de hěn gānjìng.
He BA room hit-sweep DE very clean
“He cleaned the room and the result is that the room
is very clean.”
Two kinds of intransitive verbs:
subject is agentive or not
Sam worked.
agentive
Sam fell (by accident).
non-agentive
• Unaccusative: an intransitive verb whose subject is not
agentive.
– Because the noun phrase would have been accusative if the verb
were transitive?
• Unergative: an intransitive verb whose subject is agentive.
– Because the noun phrase would have been ergative if the verb were
transitive?
• Confusing terminology by David Perlmutter and Paul
Postal.
• Highly influential and insightful contribution to linguistic
theory also by David Perlmutter and Paul Postal.
Consequences of Unaccusativity or
Agentivity
• English: Resultative secondary predication:
*He screamed hoarse.
?He worked to exhaustion.
He worked himself to exhaustion
It broke to pieces.
It froze solid.
Consequences of Unaccusativity or
Agentivity: German Impersonal Passive
http://www.wm.edu/CAS/modlang/gasmit/grammar/passive/impspass.htm
Hier wird nicht geparkt.
No parking here.
Im Gang wird nicht geraucht.
No smoking in the corridor.
Es wurde viel getanzt und gesungen.
There was lots of dancing and singing.
Works with agentive verbs only.
Not with break, fall, etc.
Consequences of Unaccusativity:
Italian partitive clitics
•
http://www.sfu.ca/person/dearmond/405/405.ergative.unaccusative.htm
Sono passate tre settimane.
Are passed three weeks
Three weeks have passed.
Ne
sono passate tre.
Of-them are passed three
Three of them have passed.
Ne
sono arrivati(?) tre.
Of-them are arrived
three
Three of them have arrived.
* Ne
hanno telefonato(?) tre.
Of-them have phoned
three
Three of them have arrived.
Importance of unaccusativity
• Non agentive subjects, direct object, subjects of
passives:
– The water froze solid.
– He hammered the nail flat.
– The nail was hammered flat.
• Agentive subjects and subjects of active, transitive
verbs.
– He hammered the nail exhausted.
• Doesn’t mean that he became exhausted as a result of
hammering the nail.
– He screamed hoarse.
• Doesn’t mean that he became hoarse as a result of screaming.
Importance of Unaccusativity
• Non-agentive subjects behave like direct
objects.
• Passive subjects correspond to direct objects
of active sentences.
• The Unaccusative Hypothesis (Perlmutter
and Postal): Maybe non-agentive subjects
are direct objects at some level of
representation.
Example of insight from the
unaccusative hypothesis
• Why can’t German unaccusative verbs
become impersonal passives?
• They are already passive! The non-agentive
subject was at some point an object that got
promoted.
An additional observation
• Theme and patient arguments alternate between
being in subject position and being in object
position:
–
–
–
–
–
–
Sam broke the glass.
The glass broke.
Problems exist.
There exist problems.
Many people dwell in this village.
In this village dwell many people.
• Agents do not alternate between being subject and
object. They are always subjects in active
sentences and obliques in passive sentences.
Accounting for the observation
• Chomsky:
– Themes and patients start out in object position
in deep structure. They move up to subject
position if it is open.
– Agents originate in subject position.
– Movement is in only one direction: up from
object to subject (so that the NP c-commands
the place it came from).
Accounting for the observation
• Bresnan
– Themes and patients are linked to an
underspecified grammatical function (L. Levin,
1986).
– There can be exactly one subject for each verb.
– The underspecified function can fully specified
as subject or object, depending on whether the
subject function has already been taken or not.