Phrase structure in human language is generally "endocentric," in the sense that it is constructed based on a certain central element–called the "head" of a phrase–which determines the essential properties of the phrase, accompanied by other non-central elements, thus forming a larger structure. The chapter explores a few different interpretations of Merge and related operations, and discusses some implications for comparative syntax, particularly Japanese syntax. It focuses on the operation Merge, which is assumed in bare phrase structure theory to be the fundamental operation in human language, and discuss its properties and problems. Finally, we reconstruct X-bar theory in a way that makes no reference to the notion of bar-level but instead makes the notion 'head of the central one.Ībstract: This chapter reviews the history of modern linguistics, to see how these characteristics have been captured by various different components of grammar. We show that, as constraints on phrase-structure rule systems, the X-bar conditions have hardly any effect on the descriptive power of grammars, and that the principles with the most chance of making some descriptive difference are the least adhered to in practice. We then consider recent proposals to 'eliminate' base components from transformational grammars and to reinterpret X-bar theory as a set of universal constraints holding for all languages at D-structure, arguing that this strategy fails. We state and discuss six conditions that encapsulate the claims of X-bar theory: LEXICALITY-each nonterminal is a projection of a preterminal SUCCESSION-each X n + 1 dominates an X n for all n ≥ 0 UNIFORMITY-all maximal projections have the same bar-level MAXIMALITY-all nonheads are maximal projections CENTRALITY-the start symbol is a maximal projection and OPTIONALITY-all and only nonheads are optional. In this paper we will demonstrate that a formalization of its content reveals very little substance in its claims. The aim of this paper is to undertake a systematic examination of the content of X-bar theory and its consequences for language description.Abstract: X-bar theory is widely regarded as a substantive theory of phrase structure properties in natural languages.
#Xbar theory how to#
How to reconstruct the X bar theory of phrase structure?įinally, we reconstruct X-bar theory in a way that makes no reference to the notion of bar-level but instead makes the notion ‘head of’ the central one.∗ 1 f 1. X-bar theory captures the insight that all phrases share some essential structural properties.
It is a theory about the internal structure of syntactic constituents which was originally intended to place constraints on the power of phrase structure rules. X-bar theory is a generative theory of language conceived by Noam A. A major factor in this is that parsing is most commonly evaluated against the Penn Treebank or various dependency annotated corpora, neither of which would be considered X-bar structures. The simplest answer is that high performance NLP applications do not use X-bar theory as an explicit representation. It embodies two independent claims: one, that phrases may contain intermediate constituents projected from a head X and two, that this system of projected constituency may be common to more than one category (e.g., N, V, A, P, etc.). In linguistics, X-bar theory is a theory of syntactic category formation. You can type it anywhere in your document. Type x where you want the X-bar to appear. It’s a blue icon with a white “W.” You’ll typically find it on the Dock or in the Applications menu. Select “Top Border” from the drop-down menu. Click the down arrow on the “Borders” button in the “Paragraph” section of the “Home” tab. Type the text you want to overline into your Word document and make sure the “Home” tab is active on the ribbon bar. Click Accent on the Design tab > Structures group.Type D in the equation box, then select it.
Select Insert New Equation from the bottom of the list.Go to the Insert tab > Symbols group (far right), then click Equation.How do you put a bar over a letter in Word? Every phrase has a head, and each phrase might contain other phrases in the complement or specifier position. X-bar theory makes the simple proposal that every phrase in every sentence in every language is organized the same way. What is the X bar theory in linguistics?.