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  • So let’s talk about trees. But not the kind with flowers or fruit or leaves. No, I mean

  • the trees that underlie our sentences, the ones that build up the structure that our

  • words slot into and let us build bigger meanings. Every time you build a sentence, every time

  • someone talks to you, youre growing one of these trees. All I’ve just been saying

  • has planted a little grove of language in your mind. So let’s do some climbing! I’m Moti

  • Lieberman, and this is The Ling Space.

  • There’s a whole branch of linguistics that’s devoted to looking at the structure of sentences,

  • known as syntax. But why do we even bother?

  • Can’t we just stack our words one on top of another like pancakes

  • to build some delicious meanings?

  • Well, there has to be some structure, or else we’d be able to work back from a smashed-up wreck

  • of a sentence like “a threatening hand is who Angel missing lawyer the is,” and have

  • it get the same meaning as the original, “The lawyer who is missing a hand is threatening

  • Angel.” Clearly, one of those is a good sentence of English, and the other one is just gibberish

  • that happens to be made up of English words. So structure must matter.

  • But what kind of structure do we need? Well, whatever hypothesis we come up with, it’s

  • got to be really flexible. That's because it has to capture all the variation in how all the

  • different languages in the world put together all their different sentences. We don’t want to say

  • Icelandic speakers have one basic way of making sentences, but Telugu speakers have a second

  • one, and Cree speakers a third. Building sentences with their own internal structures is something

  • common to every language of the world, and so an Icelandic baby dropped off in southeastern

  • India will learn Telugu syntax just fine. That’s because the basic framework of syntax

  • is universal. In fact, it’s part of Universal Grammar, the linguistic knowledge all people share.

  • But with all the surface differences, finding something that can branch its way through

  • every human language isn’t obvious. Not only does it have to be flexible, it also

  • has to be abstract.

  • So, here are a lot of hypotheses out there, but one of the most commonly talked about

  • ones, is called X’ theory, first proposed in the early 70s. The X in X’ doesn’t

  • stand for anything; it’s a variable, like in algebra. We can use that

  • variable to make a basic structure, a template, like this: X can stand for any noun or verb

  • or adjective or any category you want to build a phrase around. You end up with chunks of

  • syntax that can be stacked and connected together, and you do it in a way that’s flexible enough to communicate

  • anything that you want, in any language that you want.

  • This gets a lot clearer when you start looking at some examples. Let’s start with something

  • really simple: a name, likeCordelia.” Okay, so in your mental lexicon, where you

  • store all your words, each term belongs to a syntactic category - which is like a part of speech,

  • so a noun, an adverb, etc. “Cordeliais a noun, so when we want to putCordelia

  • in our X’ tree, we replace the Xs with Ns for nouns. In this phrase,

  • Cordelia is thehead”, which is the part of the phrase with the most content and meaning.

  • Because Cordelia’s the head of the phrase, and because it’s a noun, the whole thing

  • will become a noun phrase, or NP. Great! Done. Except, not really. This might work if we

  • never said anything more than bare nouns and verbs and things, but natural language is

  • a lot more involved than that. So sometimes all you want to say is Cordelia, but sometimes

  • you might want to say nice things about Cordelia. Maybe you want to say, “The amazing Cordelia.”

  • Where did those other words fit in?

  • Well, that’s where thebarpart of X’ theory comes to the rescue. So between the

  • head and phrase level, we introduce one more layer of complexity: that's the bar level, which is written

  • with an apostrophe next to the letter that represents the head. The bar level is an intermediate, repeatable

  • stage in the template that allows us all the flexibility we need to

  • build bigger phrases and sentences. Let’s see how this works.

  • Since theyre still all still associated with the noun - theyre all to do with Cordelia

  • - you need to have extra room for those extra words in your noun phrase. So they need to get nestled into

  • the NP, and that’s where the N’ comes in. Now your sentence is shaping up.

  • But wait. Why bother having these intermediate stages at all? Even if we know all these words

  • come together to make a noun phrase, why put in all these extra levels of structure? Why

  • not just put in an NP at the top, and then different labels for all the words below - so an N for the noun,

  • an A for the adjective, etc. That’d be easier, right?

  • Wellhere’s the thing. The reason we needed syntax in the first place was to give

  • structure to how come sentences mean what they do, and have the word order that they

  • do. All the information about what a sentence means, that is the syntax, and it has to be

  • visible in our diagrams, why bother drawing trees in the first place, right?

  • So we end up needing to branch things off two by two with bar levels,

  • otherwise we wouldn’t know what parts go with other parts. We can even put as many

  • bar levels into the structure as we want, so it'll work for any kind of sentence. For

  • example, if we saidthe quirky, supremely intelligent Fred,” and there was no internal

  • structure, so everything was just flat, we wouldn’t know that supremely was supposed

  • to go with intelligent, and not with quirky. We wouldn’t be able to come up with any

  • rules to stop these things. All the rules, everything that’s okay and not okay,

  • has to be seen in the structure.The bar levels give us a hierarchy that allows us to make

  • sense of things like this. Now, we knowsupremelygoes withintelligent”, and that you

  • can’t just pull words out willy-nilly to make nonsense sentences.

  • What X’ theory shows us is the way that we can build structure

  • in order to capture all the facts of language, along with the flexibility to add whatever

  • we like. They let us add potentially infinite parts before the head, likeThe bespectacled

  • bookish Brit Wesley,” or after it, as inthe vampire with a soul and a big black

  • coat.” And this sort of syntax also lets us capture facts about how we form larger

  • sentences, as questions, find ambiguity, and all sorts of other things, which well

  • talk about in the future.

  • Linguists today have a lot of other hypotheses about syntax, too, but X’ is a great place

  • to start because it shows all of the hallmarks of why syntax is real and useful. It can be

  • applied to any type of word, in any type of sentence, in any type of language. It’s

  • just a template: a head with a phrase and as many intermediate stages as you’d like.

  • But by using that one little template, and putting it in every time you make a phrase,

  • you can shape a whole world of language. Shaping those little trees can tell you what

  • language is. And that’s worth the climb.

  • So weve reached the end of the Ling Space for this week, but if you were making your

  • own happy little trees, you learned that sentences must have an internal structure to them if were

  • going to capture the facts we know about them; that the basic template of that structure

  • needs to be flexible and universal; that the template in X’ theory consists of a head,

  • a phrase, and as many bar levels as you need to fit all the words you have; and that the

  • structure should branch off two-by-two to fit the facts about hierarchy that we feel are true.

  • The Ling Space is written and produced by me, Moti Lieberman. It’s directed by Adèlelise

  • Prévost, our production assistant is Georges Coulombe, our music and sound design is by

  • Shane Turner, and our graphics team is atelierMUSE. Were down in the comments below, or you

  • can take the discussion back over to our website, where we have more information on this

  • topic. Check us out on Tumblr, Twitter, and Facebook, and if you want to keep expanding

  • your own personal Ling Space, please subscribe. And well see you next Wednesday. /seləvu/!

So let’s talk about trees. But not the kind with flowers or fruit or leaves. No, I mean

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B1 cordelia syntax structure noun phrase template

Syntactic Trees and X' Theory

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    Sh, Gang (Aaron) posted on 2016/01/14
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