Week4-1Syntax

Syntax

Language is more than a bag of words!

Grammar rules apply to the categories and groups of words, not individual word

Example - a sentence includes a subject and a predicate

Learn the new word and its syntactic usage.

Defining the POS

What do nouns typically have in common?

can be preceded by “the”

Verbs can be preceded by can’t.

Adjectives can be between “the” and a noun

Determiners

Constituents

Constituents are continuous

Constituents are no-crossing, if 2 constituents share 1 word, then one of them must completely contain the other

Each word is a constituent of itself

Constituent tests

coordination test: if 2 parts can be connected by conjunctions, they are both constituents

pronoun test: constituents can be replaced by corresponding pronouns

question by repetition test

I have seen blue elephants

blue elephants? Yes

seen blue? No

seen blue elephants? Yes

topicalization test

Blue elephants, I have seen.

question test:

What have I seen?

deletion test

semantic test

…

How to generate sentences?

One way: tree structure

Generate the tree structure first

Fill the leaf nodes with terminals

PP ambiguity

The boy saw the woman with the telescope.

Repetition(*)

JJ* = a sequence of zero or more JJ

Are all sequences of adjectives allowed? No

a big red house YES

a red big house NO

Adjective ordering in English depends on semantics!

Nested sentences

Birds fly. vs. I believe that birds fly.

Example

- I don’t recall whether I took the dog out.

- Do you know if the mall is still open?

Recursion

S can generate VP, and VP can generate S.

NP can generate PP, and PP can generate NP.

Conjunctions of NPs and PPs

Meta-patterns(X-bar theory)

Auxiliaries

Is “Aus V” a constituent? YES, pass the conjunction test.

I have seen elephants and will remember them forever.

Recursion

VP -> Aux VP

Raj may have been sleeping.