Linguistic grammar homework.
TOPICS
I. Phrases and Hierarchical structure
A. Words form larger units
B. How we represent units
II Phrase structure rules
A. What phrase structure rules represent
B. The form of PS rules
C. Making PS rules general
D. One-word phrases
III. Recursion
Notes!!!!!
1
I. Phrases and Hierarchical structure
A. Words form larger units
I. Phrases and Hierarchical structure
A. Words form larger units
Evidence: ambiguity
Best Western is a large motel chain.
[large motel] chain
large [ motel chain]
.
I. Phrases and Hierarchical structure
A. Words form larger units
Evidence: ambiguity
Best Western is a large motel chain.
[ [large motel] chain ]
[ large [ motel chain] ]
.
I. Phrases and Hierarchical structure
· °
• • • •
• • • •
[ [large motel] chain ] [large [ motel chain] ]
I. Phrases and Hierarchical structure
A. Words form larger units
Evidence: ambiguity
Best Western is a large motel chain.
[[large motel] chain]
[large [ motel chain]]
We can’t explain this without the concept of phrase—units larger than the word.
B. How we represent units
B. How we represent units
labeled brackets
[NP the students [PP in [NP the class ]]]
B. How we represent units
labeled brackets
[NP the students [PP in [NP the class ]]]
Labelled brackets show:
-the units
-the type of units (groupings and category)
-hierarchical structure: one phrase contains another
II Phrase structure rules
II Phrase structure rules
Phrase structure rules represent:
-generalizations about how phrases are constructed
II Phrase structure rules
What is the form of PS rules?
-rewrite rules:
NP Det – N- PP
the book about Japanese
II Phrase structure rules
What is the form of PS rules?
-rewrite rules:
NP Det – N- PP
the book about Japanese
How are the rules applied?
II Phrase structure rules
What is the form of PS rules?
-rewrite rules:
NP Det – N- PP
the book about Japanese
How are the rules applied?
(How are applications of rules represented to show the structure of individual sentences?)
II Phrase structure rules
One alternative:
A. Represent a sentence as a collection of
rewrite rules, with words plugged in:
“Messages with no attachments arrived from Sweden”
II Phrase structure rules
One alternative:
A. Represent a sentence as a collection of
rewrite rules, with words plugged in Sn NP1 – VP1
NP1 N1 – PP1
PP1 P1 – NP2
NP2 D1 – N2
VP1 V1 – PP2
NP3 N3
II Phrase structure rules
One alternative:
“Messages with no attachments arrived from Sweden”
A. Represent a sentence as a collection of
rewrite rules and rules of lexical insertion:
Insert:
N1 messages D1 no
N2 attachments V1 arrived
N3 Sweden
P1 with
P2 from
II Phrase structure rules
“Messages with no attachments arrived from Sweden”
A second alternative:
B. Convert each symbol to a set of labeled
brackets:
[S [NP1 [N1 messages] [PP1 [P1 with] [NP2 [D no]
[N2 attachments]]]] [VP1 [V1 arrived] [PP2 [P2 from]
[NP3 [N3 Sweden]]]]]
II Phrase structure rules
A third alternative:
C. Use Nodes and branches to represent the application of rules:
S = S NP - VP
NP VP
II Phrase structure rules
A third alternative:
C. Use Nodes and branches to represent the application of rules:
S NP N - PP
NP VP
N PP
BRANCHES DO THE REWRITING:
NP => DET - N - (PP)
the students in the class
NP
Det
the
BRANCHES DO THE REWRITING:
NP => DET - N - (PP)
the students in the class
NP
Det N
the students
BRANCHES DO THE REWRITING:
NP => DET - N - (PP)
the students in the class
NP
Det N PP
the students in the class
BRANCHES DO THE REWRITING:
NP => DET - N - (PP)
the students in the class
NP
Det N PP
the students in the class
BRANCHES DO THE REWRITING:
NP => DET - N - (PP)
the students in the class
NP
Det N PP
the students in the class
II Phrase structure rules
How can the rules be general enough to cover different cases?
II Phrase structure rules
How can the rules be general enough to cover different cases?
• Optional elements
• Two or more different elements can occupy the same position.
II Phrase structure rules
Optional elements:
The rule:
NP Det – N- PP
does not cover these sentences:
Lee ordered pizza.
Carey ordered red wine.
II Phrase structure rules
NP Det – N- PP
This rule does not cover these sentences:
Lee ordered pizza.
Carey ordered red wine.
(Why not?)
II Phrase structure rules
NP Det – N- PP
This rule does not cover these sentences:
Lee ordered pizza.
Carey ordered red wine.
(Why not?) These sentences are missing Determiners in the NPs; the rule given above would predict these phrases to be illformed.
II Phrase structure rules
Solution: modify the rule system to allow optional elements. Here, NP contains N; it may also contain other words, but they’re optional:
NP (Det) – N- (PP)
II Phrase structure rules
Can there be a one-word phrase?
II Phrase structure rules
Can there be a one-word phrase?
Yes:
Lee ordered pizza.
This sentence contains two one-word NPs.
II Phrase structure rules
• Two or more different elements can occupy the same position.
ate a cookie VP V – NP
said Mary left VP V – S
II Phrase structure rules
• Two or more different elements can occupy the same position.
ate a cookie VP V – NP
said Mary left VP V – S
VP S
NP
II Phrase structure rules
• Two or more different elements can occupy the same position.
ate a cookie VP V – NP
said Mary left VP V – S
VP S
NP
(see p. 39)
III. Recursion
III. Recursion
What is recursion? The property of reproducing or regenerating a phrase within another phrase of the same type
III. Recursion
What is recursion? The property of reproducing or regenerating a phrase within another phrase of the same type
John
John’s sister
John’s sister’s mother
John’s sister’s mother’s cousin
III. Recursion
How do PS rules represent recursion?
III. Recursion
John’s sister
III. Recursion
John’s sister NP
Poss NP N
sister
N
John’s
III. Recursion
John’s sister’s mother NP
Poss NP N
mother
Poss NP N
sister’s
N
John’s
III. Recursion
John’s sister’s mother NP
Poss NP N
mother
Poss NP N
sister’s
N
John’s
III. Recursion
John’s sister’s mother’s cousin
Can you draw the tree?
III. Recursion
NP
PossNP N
PossNP N cousin
PossNP N mother’s
N sister’s
John’s
III. Recursion
What PS rules are needed to generate this phrase?
John’s sister’s mother’s cousin
III. Recursion
What PS rules are needed to generate this phrase?
John’s sister’s mother’s cousin
NP => (Poss NP) N
Poss NP => (Poss NP) N
IV. Summary
1. Words form larger units
2. Rewrite rules generate units.
3. The information in PS rules can be represented visually in different ways: with labeled brackets or graphically with tree diagrams.
4. Properties of the system:
IV. Summary
Properties of the system:
• rules can be made general by including optional elements in parentheses.
example: NP (D) – N – (PP)
• rules are potentially recursive: a phrase of a given type can be embedded within another phrase of the same type.
example: PP P - PP
V. Practice with PS Rules and Trees
V. Practice with PS Rules and Trees
Embeddings:
1. Joan said Marti discovered the answer.
2. Pam believes Joan said Marti discovered the answer.
V. Practice with PS Rules and Trees
V. Practice with PS Rules and Trees
V. Practice with PS Rules and Trees
Embeddings:
a desk with a drawer
a desk with a drawer with no handle
55
V. Practice with PS Rules and Trees
56
V. Practice with PS Rules and Trees
57
V. Practice with PS Rules and Trees
Structural ambiguity
V. Practice with PS Rules and Trees
Structural ambiguity
a blouse with some beads from France
V. Practice with PS Rules and Trees
V. Practice with PS Rules and Trees
V. Practice with PS Rules and Trees
Structural ambiguity
Carey bought blueberries from Greenbank Farm.
V. Practice with PS Rules and Trees
V. Practice with PS Rules and Trees