11 votes
Accepted

Why isn’t it obvious that the grammars of natural languages cannot be context-free?

Imagine a very simple CFG that only handles nouns and verbs. S → N V N → dogs | cats | Alice | Bob V → walk | play | eat Right now this can't handle agreement. But it can with a small change: S → ...
Draconis's user avatar
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10 votes
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Intuitive English example of why linguists think natural language grammar is stronger than CFL?

I don't personally believe that CFL are insufficient, but among linguists who care about weak generative capacity (probably most don't care about the issue), the consensus seems to be that they are. ...
Greg Lee's user avatar
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8 votes
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What is the “Chomsky hierarchy”?

In the 50's, Chomsky set out to devise a mathematical theory of language, which resulted in classifying kinds of production rules. For example, if all rules in a grammar are of the form A → a A, or A →...
user6726's user avatar
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5 votes

Is language a formal system?

No, natural language is not a formal system. Some rather interesting theories about natural langages are formal systems. But to confuse a theory with the phenomena that it is a theory of is ...
Greg Lee's user avatar
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5 votes
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Is language a formal system?

The author has mistaken language and grammar, and that criticism isn't valid for any period of generative phonology. Grammar is a cognitive ability which can be modeled as a particular kind of formal ...
user6726's user avatar
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4 votes

What is the “Chomsky hierarchy”?

I’m still learning, but I can give it a stab. These ideas probably originate from Chomsky’s work in the late 1950’s to mid 1960’s. I do not know how it precipitated, but it appears Chomsky’s teacher ...
Julius Hamilton's user avatar
4 votes

Why isn’t it obvious that the grammars of natural languages cannot be context-free?

Nothing in mathematics is ever obvious until after it is proven. 1.1 This is one reason English not being a CFG is not "obvious". A right-linear grammar can generate English, because a ...
user6726's user avatar
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3 votes

Combinatory categorial grammar for English

Are you aware of CCGbank (Hockenmaier, 2003)? This is the largest-scale corpus of English text annotated with CCG categories, consisting of ~1 million tokens of text, and is derived semi-automatically ...
jogloran's user avatar
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3 votes

What is terminology for the difference between, for instance, "see" and "sees"?

There's no terminology that generically describes all such differences, but the most likely kind of difference, what I suppose you have in mind, relates to the idea of a "verb form" – under ...
user6726's user avatar
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2 votes
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How to diagram a sentence containing a sentence adverb?

Simplified Tree Diagram of Supplementary Adjunct:
BillJ's user avatar
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2 votes

Are all grammar formalisms either dependency or constituency grammars?

In a manner of speaking, yes. The analysis of phrases into immediate constituents is not really a matter of theory, but more a matter of fact, which any grammatical theory must provide for. So, in ...
Greg Lee's user avatar
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2 votes
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All the strings X2Y where X and Y are composed of 0s and 1s, X ≠ Y

If you generate (or parse, same thing in reverse) both of the strings at the same time, one token at a time, your grammar can only be in a limited number of states (strings are (still) the same, ...
Agnes's user avatar
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2 votes

Can anyone explain me the structure of the FCFG grammar

The NLTK book, chapter 10, which provides some theoretical background to the implementation, references NLTK ch. 9, where the feature grammar is introduced. Have you read these articles? Ch. 9 ...
Natalie Clarius's user avatar
2 votes
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"in relation to which" - what type of subordinated clause and is this conjunction somehow distinct?

It is a relative clause. A plot of land is acting as the lexical head of the RC, and in relation to was 'moved' to before the relative pronoun (not conjunction) which through the process of pied ...
WavesWashSands's user avatar
2 votes

Is there a formal system in Linguistics like Boolean algebra to reduce the grammar rules of a language to minimum items ignoring semantics?

There are various such systems. You could start with the systems of The sound pattern of English and Aspects of the theory of syntax, because they were widely used and have learnable formalisms. A ...
user6726's user avatar
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2 votes

Is there any connection between formalism and generativism

By "generativism", I assume you mean "the theory of Generative Grammar". This is a theory promulgated by Chomsky starting, in one form, in 1951. It came to be known as "...
user6726's user avatar
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2 votes

Is English modeled as a deterministic CFL or a CFL?

No natural language is deterministic. What book mentions LR parsers for English? There might be some “controlled languages” based on English that are deterministic, but a broad-coverage parser is ...
Atamiri's user avatar
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1 vote
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Does simple type theory distinguish between those common nouns that are used as arguments and those that are used as predicates?

For general use as an argument: You need EITHER a silent determiner (or another head) that converts <e,t> to either <<e,t>,t> or e OR a theory of coercion that performs its function ...
Viridianus's user avatar
1 vote

All the strings X2Y where X and Y are composed of 0s and 1s, X ≠ Y

Agnes has already explained the intuition why the language is context-free. Here are three more concrete tips that may be helpful:
Keelan's user avatar
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1 vote

Can we build semantic mappings for CFG same as we do in CCG?

If you can get from CG (Categorial Grammar) to the semantic mappings you want, I can show you a way to get from CFG (Context Free Phrase Structure Grammar) to CG. So the answer to your question might ...
Greg Lee's user avatar
  • 12.5k
1 vote

Intuitive English example of why linguists think natural language grammar is stronger than CFL?

One example is generating relative clauses parses with an intuitive structure. In a CFG, we'd need to define new rules to deal with the syntax of the relative clause in the following sentence, since "...
William Merrill's user avatar
1 vote

How can PSG describe the vertical dimension of sentence structure?

Substitution versus Replacement Hans Reichenbach in his classic Elements of Symbolic Logic distinguishes between substitution for a variable and replacement of an expression. Substitution is uniform,...
Greg Lee's user avatar
  • 12.5k
1 vote

Formal definition of English grammar

Perhaps anyone here would know about loosely equivalent sources that like this one are fit for direct use by software. I have also been pursuing this question for years, and I believe this is the ...
Julius Hamilton's user avatar

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