Popular in Course
Popular in Linguistics
This 11 page Class Notes was uploaded by Erich Mueller on Sunday September 6, 2015. The Class Notes belongs to LIN 380L at University of Texas at Austin taught by Staff in Fall. Since its upload, it has received 70 views. For similar materials see /class/181577/lin-380l-university-of-texas-at-austin in Linguistics at University of Texas at Austin.
Reviews for SYNTAX I
Report this Material
What is Karma?
Karma is the currency of StudySoup.
Date Created: 09/06/15
Syntax 380L September 12 2003 Phrase Structure Rules Structure within the NP 1 De nitions 1 a tree for the brown fox sings A Bc sin gs D E the F G brown fox 0 Linguistic trees have nodes The nodes in 1 are A B C D E F and G 0 There are two kinds of nodes internal nodes and terminal nodes The internal nodes in 1 are A B and E The terminal nodes are C D F and G Terminal nodes are so called because they are not expanded into anything further The tree ends there Terminal nodes are also called leaf nodes The leaves of 1 are really the words that constitute the sentence the brown fox sings ie the brown fox and sings 2 a A set of nodes form a constituent iff they are exhaustively dominated by a common node b X is a constituent on iffX is dominated by Y c X is an immediate constituent on iffX is immediately dominated by Y Notions such as subject object prepositional object etc can be de ned structurally So a subject is the NP immediately dominated by S and an object is an NP immediately dominated by VP etc 3 a If a node X immediately dominates a node Y then X is the mother of Y and Y is the daughter ofX b A set of nodes are sisters if they are all immediately dominated by the same mother node We can now de ne a host of relationships on trees 7 grandmother granddaughter descendant ancestor etc Another important relationship that is de ned in purely structural terms is cicommand 4 A cicommands B if and only if A does not dominate B and the node that immediately dominates A dominates B cicommand is used in the formulation of Condition C a principle used to determine what a pro noun may not refer to O CONDITION C 5 A pronoun cannot refer to a proper name it cicommands Note that Condition C is a negative condition It never tells you what a particular pronoun must refer to It only tells you what it cannot refer to In general if a pronoun cannot refer to a proper name despite agreeing in gender and number you can conclude that the pronoun cicommands the proper name 0 The NO CROSSING BRANCHES CONSTRAINT 6 Ifone node X precedes another node Y then all descendants ofX must also precede Y and all descendants on 2 How to grow trees Where do the trees that we use to analyze linguistic structure come from In a way they arejust representations of facts that exist out in the world 7 the facts that we can discover using constituency test So one way to make trees is by doing empirical work 7 taking a sentence applying various constituency tests to the words in the sentence and then drawing a tree based on the results of our tests This empirical method is ultimately the only correct way to deduce tree structure However in most cases we can simplify things considerably by using Phrase Structure Rules Phrase Structure Rules are rules of the sort X gt Y Z This rule says take the node X and expand it into the nodes Y and Z Alternately going from right to left or from below it says if you have a Y and a Z next to each other you can combine them to make an X Phrase structure rules can be categorial ie rules that expand categories into other categories or they can also be lexical ie rules that expand category labels by word lexical items 0 A grammar can then be thought ofas a set ofphrase structure rules categorial rules plus lexical rules The categorial rules can be thought of as part of the syntax and the lexical rules as part of the lexicon 21 Some Phrase Structure Rules for English 7 Categorial Rules a S gt NP Modal VP b VP gt V AP PP c AP gt ADVP A 1Such phrase structure rules are called Context Free Grammars CFO and were invented by Noam Chomsky in 1956 A closely related model was used by Panini to describe the grammar of Sanskrit in around 500 BC 2Why must we have at least some lexical rules d ADVPAADV e PP gtPNP f NP gtDN 8 Lexical Rules a N gt girl b N gt boy c Adv gt incredibly d A gt conceited e V gt seem f Modal gt must g P gt to h D gt that i D gt this Some sentences these rules Will generate 9 a This boy must seem incredibly conceited to that girl b This boy must seem incredibly conceited to this girl c This boy must seem incredibly conceited to that boy 1 This boy must seem incredibly conceited to this boy e This girl must seem incredibly conceited to that girl f This girl must seem incredibly conceited to this girl g This girl must seem incredibly conceited to that boy h This girl must seem incredibly conceited to this boy How many more sentences Will these rules generate 0 Optional constituents How do we handle cases like 10 This boy must seem incredibly stupid 22 Introducing in nity We know that human languages can contain sentences of arbitrary length Consider ll Which stands for an in nite number of sentences ll He believes that he believes that he believes that he believes that he ate pizza So if all of human language is to be generated by a set of phrase structure rules the relevant set of phrase structure rules should generate an in nite number of sentences How can that be done Let us try to analyze l 1 starting With a more manageable 12 12 He believes that he ate pizza We start with the following categorial rules 13 a S gtNPVP b VP gtVS c S gtCOMPS d VP gtVNP We need the following lexical rules 14 a NP gt he b NP gt pizza c V gt ate cl V gt believes e COMP gt that Now we can generate 12 This is shown in 15 15 S NP VP he V S believes COMP S that NP VP he V NP ate pizza But is 12 all that the rules in l 3 and 14 will generate How many sentences will 1 3 and 14 generate 221 Overgeneration The rules in l 3 and 14 will also generate sentences see the structure below like 1 6 He ate that he believes pizza S NP VP he V S ate COMP S that A NP VP he A V NP believes pizza How can we constrain phrase structure rules so that such overgeneration does not take place 3 Noun Phrases So far we have seen two kinds of categories wordilevel categories such as N V A P etc somewhat imprecisely words and phraseilevel categories such as NP VP AP PP etc somewhat imprecisely sequences of words which can stand on their own We will now investigate if these two kinds of categories are all we need a third category which lies in between words and full phrases Consider the following NP 1 7 the king of England We feel quite con dent saying that the king of England is an NP What else can we say about its structure There seems to be a lot of evidence that of England is a PP It can be coordinated shared in shared constituent coiordination It can also function as a sentence fragment and be preposed 18 a the king pp of England and pp of the empire coordination b He is the king and she is the queen pp ofEngland shared constituent coordination c A Was he the king of Livonia B No pp of England sentence fragment 1 pp Ofwhich country was he the king At this point we have two options 19 NP NP D D N PP the N p the kin A g P NP king A P NP of England of England There is evidence from constituency tests that the sequence of words king of England forms a constituent 0 king of England can undergo coordination with another similar sequence 21 Vivian dared defy the king ofEngland and ruler of the Empire 0 king of England can serve as the shared constituent in shared constituent coiordination 22 Edward was the last and some people say the best king of England 0 There is a proform that replaces sequences like king of England 23 The present king of England is more popular than the last one So king of England forms a constituent that excludes the Thus we have evidence for the tree in This evidence doesn t actually rule out the tree in 19 It is not easy to rule out 19 on the basis of the discussion so far However an assumption that natural language structures only involve binary branching could be used to block structures like 19 31 What kind of constituent is king of Englandquot In other words what is the name of the node labeled 7 in 20 7 Let us assume that it is an NP We nd that this assumption is problematic in many ways 0 king of England does not have the distribution of normal full noun phrases Normal NPs can occur in subject position in object position and as a prepositional object king of England cannot appear in any of these positions 24 a subject i The king of England invaded several countries ii King of England invaded several countries b object i I saw the king of England on the T yesterday ii I saw king of England on the T yesterday c prepositional object i I didn t give any money to the king of England ii I didn t give any money to king of England 0 Consider the tree for the king of England under the assumption that king of England is also an NP 25 NP D NP the N PP king A P NP of England From this tree we can read of the phrase structure rules involved in building it They are shown in 26 26 a Categorial Rules i NP gt D NP ii NP gt N PP iii PP gt P NP b Lexical Rules i D gt the ii N gt king iii P gt of iv NP gt England Note in particular the categorial rule 26ai It has the unusual property that it expands a node label into itself Such rules are called recursive and this phenomena is called recursion So we can go from NP to D NP to D D NP to D D D NP and so on In principle using the rules in 26 we can generate NPs like those in 27 27 a the the king of England b the the the king of England c the the the the king of England Now it is very clear that none of the NPs in 27 are good noun phrases in English From this we can conclude that the categorial rule 26ai which is the source of the recursion cannot be correct So 0 king of England cannot be an NP and yet 0 king of England is a constituent of some sort Let us call nominal constituents that are bigger than words but still not full phrases N or N or Nebar Our tree now becomes 3We have already seen a case of recursion though there the recursion was in two steps 28 NP DAN the N PP king P NP of England NPs are somtimes called Nidouble bars or N N are sometimes called Nquot 4 Complements and Adjuncts Consider the phraseistructure rules responsible for generating 28 4 29 a NP gt D N b N gt N PP c PP gt P NP We see that D combines with an N to its left and forms an NP Similarly P combines with an NP to its left and forms a PP Likewise 29 says that an N combines with any PP that follows it ie any postnominal NP and forms an N But is this really the case Do the PPs in 30a b have the same relation to the N 30 a a student of Physics b a student with long hair It seems not Consider the following pattern 31 a i He is a student of Physics ii He is studying Physics b i He is a student with long hair i39 75 He is studying long hair PPs like of Physics are called complements while PPs like with long hair are called adjuncts Corresponding to this difference in terminology a structural difference is also proposed This is shown in 32 32 4From now on we will only consider the categorial rules The lexical rules are straightforward Determiner N N Adjunct N Complement In terms of phrase structure rules this is 33 a N gt D N Determiner Rule b N gt N PP Adjunct Rule c N gt N PP Complement Rule The rules in 33 make a prediction 7 if an NP contains both a complement PP and an adjunct PP the complement PP should precede the adjunct PP This prediction turns out to be true 34 a the student of Physics with long hair b the student with long hair of Physics 41 Optional Constituents of the Noun Phrase Do all NPs have to contains a determiner a noun a complement PP and an adjunct PP Well they have to contain an N otherwise they wouldn t be NPs What about the others Consider the rules in 33 If you wanted to make an NP would it be necessary to apply the Adjunct rule You could take an N and a complement PP and make an N Then you could combine the N with an adjunct PP to make another N You could but you don t have to You can now just combine your adjunctiless N with a D on its left to make an NP So NPs don t have to contain adjuncts In other words the adjunct rule is an optional rule Still the rules in 33 insist that every NP must have a determiner the Determiner rule and a complement PP the Complement rule This is howeverjust false 35 a the student b the student with long hair 35a is an NP without a complement PP 35a show that an NP without a complement PP can still take an adjunct PP How can we modify our phrase structure rules to handle these case For this purpose we will introduce new terminology A means that A is optional So we can now change our complement rule from 36a to 36b 36 a N gt N PP Old Complement Rule b N gt N PP New Complement Rule We also nd optionality of determiners cf 37a7e 37 a cheese from Greece b students c students with long hair 1 students of physics e students of physics with long hair However this optionality is lexically determined ie it only works for certain nouns 7 noncount nouns and plural count nouns but not singular count nouns 38 a Student likes pizza b Student with long hair likes pizza For such nouns we can modify the determiner rule in the way we modi ed the complement rule in 36 39 a NP gt D N Old Determiner Rule b NP gt D N New Determiner Rule However we have to think of a way to block the NPs in 38 from being generated 42 Nonibranching Phrases Consider the new complement rule 40 N gt N PP New Complement Rule This rule is really equivalent to the following two rules 41 a N gt NPP b N gt N 41a is nothing new 41b is de nitely new It tells us something unexpected According to 4lb student in the student is both an N as well as an N while student in the student of Physics is only an N not an N Similarly student in the student with long hair should be both an N as well as an N We can check to see if these predictions are true The test we will use is substitution by the N proiform one 42 a The student with long hair is dating the one with short hair b This student works harder than that one c The student of chemistry was older than the one of Physics What can coiordination tell us here 5How can we be sure that the word sequences in 37 are N39Ps 43 A bit more on N Both 43a b are responsible for the creation of N s 43 a N gt N PP Adjunct Rule b N gt N PP Complement Rule How can we be sure that the node created by the complement rule isn t Nibarl and the node created by the adjunct rule NibarZ Again by constituency test we know that only like categories can be coordinated and we nd that N created by the two different rules can be coordinated 44 the students of Chemistry with long hair and professors of Physics In addition the proiN one can refer to N s created by either rule 45 a Which student of Physics The one with long hair b Which student of Physics with long hair That one Hence we can conclude that the output of both the rules is indeed one kind of node which we call N