转换生成语法的发展过程12-5(PPT61页)
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sentences.
▪ The grammar of a language (L) will be a device
that generates all of the grammatical sentences of L and none of the ungrammatical ones.
Three models for the structure of a language
▪ ungrammatical
ungrammatical, meaningful
Which artists did you find works by interesting.
ungrammtical, non-meaningful
Furiously sleep ideas green colorless.
▪ Finite State Grammar ▪ Phrase Structure Grammar ▪ Transformational & Generative Grammar
Finite State Grammar
Suppose we have a machine (the speaker) –
▪ That has a finite number of different internal states -
an initial state a final state.
▪ That switches from one state to another by
producing a symbol.
▪ The child found the puppy.
An example of a PSG (associated with constituent analysis) :
(1) S → NP + VP (2) NP → Det. + N (3) VP → Verb + NP (4) Det. → the, a, ... (5) N. → child, puppy, ... (6) V. → found
▪ It assigns to each sentence that it generates a structural
description.
▪ It makes use of phrase structure rules.
An example of a Phrase Structure Grammar
▪ That begins in the initial state, runs through a
sequence of states and ends in the final state.
Finite State Grammar
✓ The man comes. ✓ The men come.
转换生成语法的发展过程
Introduction
The Independence of Grammar
▪ grammatical
grammatical + meaningful
Tom loves Mary.
grammtical, non-meaningful
Colorless green ideas sleep furiously.
Problems with FSGs
▪ 不能处理非连续出现的句子成分间的关系；
The old man comes.
▪ 不能反应非相邻成分间的依存关系；
What does the old man speak?
▪ 有限的意味着规则不能重复使用，会导致语法
系统过于复杂。
Phrase Structure Grammar
▪ It builds up phrases out of words and put the phrases together
into senFra Baidu bibliotekences.
▪ The kind of structural description assigned by a phrase-structure
grammar is, in fact, an immediate constituent analysis of the sentence.
language.
▪ Machine that produces such a language is called a finite state
grammar (FSG).
▪ FSG is the simplest type of grammar which, with a finite amount
State Diagram
Each node in the diagram corresponds
to a state.
The
initial state
man
comes
men
come
final
state
Finite State Grammar
▪ Language produced by such a machine is called a finite state
of apparatus, can generate an infinite number of sentences.
Properties of Finite State Grammars
▪ Such grammars allow transition from one state to
another.
▪ Each state represents the grammatical restrictions that
limit the choice of the next word.
▪ Machines that produce languages in this manner are
also known as “finite state Markov processes”.
The fundamental aim in linguistic analysis
▪ Separate the grammatical sentences from the
ungrammatical sentences.
▪ Study the structure of the grammatical
▪ The grammar of a language (L) will be a device
that generates all of the grammatical sentences of L and none of the ungrammatical ones.
Three models for the structure of a language
▪ ungrammatical
ungrammatical, meaningful
Which artists did you find works by interesting.
ungrammtical, non-meaningful
Furiously sleep ideas green colorless.
▪ Finite State Grammar ▪ Phrase Structure Grammar ▪ Transformational & Generative Grammar
Finite State Grammar
Suppose we have a machine (the speaker) –
▪ That has a finite number of different internal states -
an initial state a final state.
▪ That switches from one state to another by
producing a symbol.
▪ The child found the puppy.
An example of a PSG (associated with constituent analysis) :
(1) S → NP + VP (2) NP → Det. + N (3) VP → Verb + NP (4) Det. → the, a, ... (5) N. → child, puppy, ... (6) V. → found
▪ It assigns to each sentence that it generates a structural
description.
▪ It makes use of phrase structure rules.
An example of a Phrase Structure Grammar
▪ That begins in the initial state, runs through a
sequence of states and ends in the final state.
Finite State Grammar
✓ The man comes. ✓ The men come.
转换生成语法的发展过程
Introduction
The Independence of Grammar
▪ grammatical
grammatical + meaningful
Tom loves Mary.
grammtical, non-meaningful
Colorless green ideas sleep furiously.
Problems with FSGs
▪ 不能处理非连续出现的句子成分间的关系；
The old man comes.
▪ 不能反应非相邻成分间的依存关系；
What does the old man speak?
▪ 有限的意味着规则不能重复使用，会导致语法
系统过于复杂。
Phrase Structure Grammar
▪ It builds up phrases out of words and put the phrases together
into senFra Baidu bibliotekences.
▪ The kind of structural description assigned by a phrase-structure
grammar is, in fact, an immediate constituent analysis of the sentence.
language.
▪ Machine that produces such a language is called a finite state
grammar (FSG).
▪ FSG is the simplest type of grammar which, with a finite amount
State Diagram
Each node in the diagram corresponds
to a state.
The
initial state
man
comes
men
come
final
state
Finite State Grammar
▪ Language produced by such a machine is called a finite state
of apparatus, can generate an infinite number of sentences.
Properties of Finite State Grammars
▪ Such grammars allow transition from one state to
another.
▪ Each state represents the grammatical restrictions that
limit the choice of the next word.
▪ Machines that produce languages in this manner are
also known as “finite state Markov processes”.
The fundamental aim in linguistic analysis
▪ Separate the grammatical sentences from the
ungrammatical sentences.
▪ Study the structure of the grammatical