Parsing. Based on presentations from Chris Manning s course on Statistical Parsing (Stanford)
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- Hugo Wiggins
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1 Parsing Based on presentations from Chris Manning s course on Statistical Parsing (Stanford)
2 S N VP V NP D N John hit the ball
3 Levels of analysis Level Morphology/Lexical POS (morpho-synactic), WSD Elements used Words Words Shallow syntax parsing Full syntax parsing NER, MWE SRL Full semantic parsing Phrases Sentence Phrases Parsed trees Parsed trees
4 Buffalo
5 Parsing is a difficult task!
6 Parsing is a difficult task! ^ ^ so excited! #Khaleesi #minikhaleesi #GoT
7 Telegramese A style of writing that leaves out words that are not important The Telegraph Office: How to Write Telegrams Properly The enemy has not yet been met or even seen on account of the entanglements thrown up during the night. Enemy unmet unseen account entanglements upthrown night Sell 10,000 bushels of May wheat at $1.45 ¼. Sell barney stoke [code]
8 Ambiguities POS tags (e.g., books : a verb or a noun?) Compositional expression meanings (e.g., he spilled the beans about his past) Syntactic attachments (V N PP) (e.g., I ate my spaghetti with a fork) Global semantic ambiguities (e.g., bear left at zoo) Usually, ambiguities in one layer may be resolved in upper layers
9 Ambiguities Fed raises interest rates 0.5% in effort to control inflation.
10 Motivation Parsing may help to resolve ambiguities Parsing is a step toward understanding the sentence completely Was shown to improve the results of several NLP applications: MT (Chiang, 2005) Question answering (Hovy et al., 2000)
11 Grammar S NP VP NN interest NP (DT) NN NNS rates NP NN NNS NNS raises NP NNP VBP interest VP V NP VBZ rates Minimal grammar on Fed raises sentence: 36 parses Simple 10 rule grammar: 592 parses Real-size broad-coverage grammar: millions of parses
12 Size of grammar Number of rules less more Limits unlikely parses But grammar is not robust Parses more sentences But sentences end up with ever more parses
13 Statistical parsing Statistical parsing can help selecting the rules that best fit the input sentence, allowing the grammar to contain more rules
14 Treebanks ( (S (NP-SBJ (DT The) (NN move)) (VP (VBD followed) (NP (NP (DT a) (NN round)) The Penn Treebank Project (PTB): Arabic, English, Chinese, Persian, French, (PP (IN of) (NP (NP (JJ similar) (NNS increases)) (PP (IN by) (NP (JJ other) (NNS lenders))) (PP (IN against) (NP (NNP Arizona) (JJ real) (NN estate) (NNS loans)))))) (,,)
15 Advantages of treebanks Reusability of the labor Broad coverage Frequencies and distributional information A way to evaluate systems
16 Types of parsing Constituency parsing Dependency parsing
17 Constituency parsing Constituents are defined based on linguistic rules (phrases) Constituents are recursive (NP may contain NP as part of its sub-constituents) Different linguists may define constituents differently
18 Dependency parsing Dependency structure shows which words depend on (modify or are arguments of) which other words
19 Parsing We want to run a grammar backwards to find possible structures for a sentence Parsing can be viewed as a search problem We can do this bottom-up or top-down We search by building a search tree which is distinct from the parse tree
20 Context-free (phrase structure) grammar (CFG) G T is set of terminals N is set of variables (nonterminals) S is the start symbol (one of the variables) R is rules (productions) of the form X γ, where X is a variable and γ is a sequence of terminals and variables (possibly empty) A grammar G generates a language L=L(G)
21 Probabilistic or stochastic context-free grammars (PCFG) R: rules X γ P: P(R) gives the probability of each rule X γ R X N, P(X γ) =1 A grammar G generates a language L w T* P(w) =1
22 Soundness and completeness A parser is sound if every parse it returns is valid/correct A parser terminates if it is guaranteed to not go off into an infinite loop A parser is complete if for any given grammar and sentence, it is sound, produces every valid parse for that sentence, and terminates (For many purposes, we settle for sound but incomplete parsers: e.g., probabilistic parsers that return a k-best list.)
23 Top down parsing Top-down parsing is goal directed A top-down parser starts with a list of constituents to be built. The top-down parser rewrites the goals in the goal list by matching one against the left side of the grammar rules, and expanding it with the right side, attempting to match the sentence to be derived If a goal can be rewritten in several ways, then there is a choice of which rule to apply (search problem) Can use depth-first or breadth-first search, and goal ordering
24 Top down parsing
25 Disadvantages of top down A top-down parser will do badly if there are many different rules for the same variable. Consider if there are 600 rules for S, 599 of which start with NP, but one of which starts with V, and the sentence starts with V Useless work: expands things that are possible top-down but not there Repeated work
26 Repeated work
27 Bottom up chart parsing Bottom-up parsing is data directed The initial goal list of a bottom-up parser is the string to be parsed. If a sequence in the goal list matches the right side of a rule, then this sequence may be replaced by the left side of the rule Parsing is finished when the goal list contains just the start category If the right side of several rules match the goal list, then there is a choice of which rule to apply (search problem) The standard presentation is as shift-reduce parsing
28 Shift-reduce parsing cats scratch people with claws cats scratch people with claws SHIFT N scratch people with claws REDUCE NP scratch people with claws REDUCE NP scratch people with claws SHIFT NP V people with claws REDUCE NP V people with claws SHIFT NP V N with claws REDUCE NP V NP with claws REDUCE NP V NP with claws SHIFT NP V NP P claws REDUCE NP V NP P claws SHIFT NP V NP P N REDUCE NP V NP P NP REDUCE NP V NP PP REDUCE NP VP REDUCE S REDUCE
29 Disadvantages of bottom up Useless work: locally possible, but globally impossible. Inefficient when there is great lexical ambiguity (grammardriven control might help here) Repeated work: anywhere there is common substructure
30 Parsing as search Left recursive structures must be found, not predicted Doing these things doesn't fix the repeated work problem: Both TD and BU parsers can (and frequently do) do work exponential in the sentence length on NLP problems Grammar transformations can fix both left-recursion and epsilon productions Then you parse the same language but with different trees (and fix them post hoc)
31 Dynamic programming Rather than doing parsing-as-search, we do parsing as dynamic programming Examples: CYK (bottom up), Early (top down) It solves the problem of doing repeated work
32 Notation w 1n = w 1 w n = the word sequence from 1 to n w ab = the subsequence w a w b N j ab = the variable Nj dominating w a w b We ll write P(N i ζ j ) to mean P(N i ζ j N i ) We ll want to calculate max t P(t * w ab )
33 Tree and sentence probabilities P(t) -- The probability of tree is the product of the probabilities of the rules used to generate it P(w 1n ) -- The probability of the sentence is the sum of the probabilities of the trees which have that sentence as their yield P(w 1n ) = Σ j P(w 1n, t) where t is a parse of w 1n = Σ j P(t)
34 A treebank tree ROOT S NP VP N V NP PP N P NP N cats scratch people with claws
35 CYK (Cocke-Younger-Kasami) algorithm A bottom-up parser using dynamic programming Assume the grammar is in Chomsky normal form A BC Maintain N nxn tables µ N = number of variables, n = length of input Fill out the table entries by induction
36 After binarization ROOT N V NP PP N NP N cats scratch people with claws
37 Can 1 you 2 book 3 ELAL 4 flights 5? w1,1 w1,2 w1,3 w1,4 w1,5 1 w2,2 w2,3 w2,4 w2,5 2 w3,3 w3,4 w3,5 3 w4,4 w4,5 4 w5,5 5
38 CYK Base case Consider the input strings of length one (i.e., each individual word w i ) P(A w i ) Since the grammar is in normal form: A * wi iff A w i So µ[i, i, A] = P(A w i )
39 CYK Base case Can 1 you 2 book 3 ELAL 4 flights 5? 1.4 Aux Noun
40 CYK Recursive case For strings of words of length > 1, A * w ij iff there is at least one rule A BC where B derives the first k words (between i and i-1 +k ) and C derives the remaining ones (between i+k and j) (for each non-terminal) Choose the max among all possibilities B A C i i-1+k i+k j µ[i, j, A)] = µ [i, i-1 +k, B] * µ [i+k, j, C] * P(A BC)
41 CYK Termination The max prob parse will be µ [1, n, S] w1,1 w1,2 w1,3 w1,4 w1,5 S w2,2 w2,3 w2,4 w2,5 w3,3 w3,4 w3,5 w4,4 w4,5 w5,5
42 Top down: Early algorithm Finds constituents and partial constituents in input A B C. D E is partial: only the first half of the A A D + = A B C D E j k B C D E i j i k A B C. D E A B C D. E
43 Early algorithm Proceeds incrementally, left-to-right Before it reads word 5, it has already built all hypotheses that are consistent with first 4 words Reads word 5 & attaches it to immediately preceding hypotheses. Might yield new constituents that are then attached to hypotheses immediately preceding them Use dynamic programming.
44 Example (grammar) ROOT S S NP VP NP Papa NP Det N N caviar NP NP PP N spoon VP VP PP V ate VP V NP P with PP P NP Det the Det a
45 0 0 ROOT. S initialize Remember this stands for (0, ROOT. S)
46 0 0 ROOT. S 0 S. NP VP predict the kind of S we are looking for Remember this stands for (0, S. NP VP)
47 0 0 ROOT. S 0 S. NP VP 0 NP. Det N 0 NP. NP PP 0 NP. Papa predict the kind of NP we are looking for (actually we ll look for 3 kinds: any of the 3 will do)
48 0 0 ROOT. S 0 S. NP VP 0 NP. Det N 0 NP. NP PP 0 NP. Papa 0 Det. the 0 Det. a predict the kind of Det we are looking for (2 kinds)
49 0 0 ROOT. S 0 S. NP VP 0 NP. Det N 0 NP. NP PP 0 NP. Papa 0 Det. the 0 Det. a predict the kind of NP we re looking for but we were already looking for these so don t add duplicate goals! Note that this happened when we were processing a left-recursive rule.
50 0 Papa 1 0 ROOT. S 0 NP Papa. 0 S. NP VP 0 NP. Det N 0 NP. NP PP 0 NP. Papa 0 Det. the 0 Det. a scan: the desired word is in the input!
51 0 Papa 1 0 ROOT. S 0 NP Papa. 0 S. NP VP 0 NP. Det N 0 NP. NP PP 0 NP. Papa 0 Det. the 0 Det. a scan: failure
52 0 Papa 1 0 ROOT. S 0 NP Papa. 0 S. NP VP 0 NP. Det N 0 NP. NP PP 0 NP. Papa 0 Det. the 0 Det. a scan: failure
53 0 Papa 1 0 ROOT. S 0 NP Papa. 0 S. NP VP 0 S NP. VP 0 NP. Det N 0 NP NP. PP 0 NP. NP PP 0 NP. Papa 0 Det. the 0 Det. a attach the newly created NP (which starts at 0) to its customers (incomplete constituents that end at 0 and have NP after the dot)
54 0 Papa 1 0 ROOT. S 0 NP Papa. 0 S. NP VP 0 S NP. VP 0 NP. Det N 0 NP NP. PP 0 NP. NP PP 1 VP. V NP 0 NP. Papa 1 VP. VP PP 0 Det. the 0 Det. a predict
55 0 Papa 1 0 ROOT. S 0 NP Papa. 0 S. NP VP 0 S NP. VP 0 NP. Det N 0 NP NP. PP 0 NP. NP PP 1 VP. V NP 0 NP. Papa 1 VP. VP PP 0 Det. the 1 PP. P NP 0 Det. a predict
56 0 Papa 1 0 ROOT. S 0 NP Papa. 0 S. NP VP 0 S NP. VP 0 NP. Det N 0 NP NP. PP 0 NP. NP PP 1 VP. V NP 0 NP. Papa 1 VP. VP PP 0 Det. the 1 PP. P NP 0 Det. a 1 V. ate predict
57 0 Papa 1 0 ROOT. S 0 NP Papa. 0 S. NP VP 0 S NP. VP 0 NP. Det N 0 NP NP. PP 0 NP. NP PP 1 VP. V NP 0 NP. Papa 1 VP. VP PP 0 Det. the 1 PP. P NP 0 Det. a 1 V. ate predict
58 0 Papa 1 0 ROOT. S 0 NP Papa. 0 S. NP VP 0 S NP. VP 0 NP. Det N 0 NP NP. PP 0 NP. NP PP 1 VP. V NP 0 NP. Papa 1 VP. VP PP 0 Det. the 1 PP. P NP 0 Det. a 1 V. ate 1 P. with predict
59 0 Papa 1 ate 2 0 ROOT. S 0 NP Papa. 1 V ate. 0 S. NP VP 0 S NP. VP 0 NP. Det N 0 NP NP. PP 0 NP. NP PP 1 VP. V NP 0 NP. Papa 1 VP. VP PP 0 Det. the 1 PP. P NP 0 Det. a 1 V. ate 1 P. with scan: success!
60 0 Papa 1 ate 2 0 ROOT. S 0 NP Papa. 1 V ate. 0 S. NP VP 0 S NP. VP 0 NP. Det N 0 NP NP. PP 0 NP. NP PP 1 VP. V NP 0 NP. Papa 1 VP. VP PP 0 Det. the 1 PP. P NP 0 Det. a 1 V. ate 1 P. with scan: failure
61 0 Papa 1 ate 2 0 ROOT. S 0 NP Papa. 1 V ate. 0 S. NP VP 0 S NP. VP 1 VP V. NP 0 NP. Det N 0 NP NP. PP 0 NP. NP PP 1 VP. V NP 0 NP. Papa 1 VP. VP PP 0 Det. the 1 PP. P NP 0 Det. a 1 V. ate 1 P. with attach
62 0 Papa 1 ate 2 0 ROOT. S 0 NP Papa. 1 V ate. 0 S. NP VP 0 S NP. VP 1 VP V. NP 0 NP. Det N 0 NP NP. PP 2 NP. Det N 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 Det. the 1 PP. P NP 0 Det. a 1 V. ate 1 P. with predict
63 0 Papa 1 ate 2 0 ROOT. S 0 NP Papa. 1 V ate. 0 S. NP VP 0 S NP. VP 1 VP V. NP 0 NP. Det N 0 NP NP. PP 2 NP. Det N 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 Det. the 1 PP. P NP 2 Det. the 0 Det. a 1 V. ate 2 Det. a 1 P. with predict (these next few steps should look familiar)
64 0 Papa 1 ate 2 0 ROOT. S 0 NP Papa. 1 V ate. 0 S. NP VP 0 S NP. VP 1 VP V. NP 0 NP. Det N 0 NP NP. PP 2 NP. Det N 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 Det. the 1 PP. P NP 2 Det. the 0 Det. a 1 V. ate 2 Det. a 1 P. with predict
65 0 Papa 1 ate 2 0 ROOT. S 0 NP Papa. 1 V ate. 0 S. NP VP 0 S NP. VP 1 VP V. NP 0 NP. Det N 0 NP NP. PP 2 NP. Det N 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 Det. the 1 PP. P NP 2 Det. the 0 Det. a 1 V. ate 2 Det. a 1 P. with scan (this time we fail since Papa is not the next word)
66 0 Papa 1 ate 2 the 3 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 0 S. NP VP 0 S NP. VP 1 VP V. NP 0 NP. Det N 0 NP NP. PP 2 NP. Det N 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 Det. the 1 PP. P NP 2 Det. the 0 Det. a 1 V. ate 2 Det. a 1 P. with scan: success!
67 0 Papa 1 ate 2 the 3 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 0 S. NP VP 0 S NP. VP 1 VP V. NP 0 NP. Det N 0 NP NP. PP 2 NP. Det N 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 Det. the 1 PP. P NP 2 Det. the 0 Det. a 1 V. ate 2 Det. a 1 P. with
68 0 Papa 1 ate 2 the 3 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 0 NP. Det N 0 NP NP. PP 2 NP. Det N 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 Det. the 1 PP. P NP 2 Det. the 0 Det. a 1 V. ate 2 Det. a 1 P. with
69 0 Papa 1 ate 2 the 3 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 Det. the 1 PP. P NP 2 Det. the 0 Det. a 1 V. ate 2 Det. a 1 P. with
70 0 Papa 1 ate 2 the 3 caviar 4 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 Det. the 1 PP. P NP 2 Det. the 0 Det. a 1 V. ate 2 Det. a 1 P. with
71 0 Papa 1 ate 2 the 3 caviar 4 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 Det. the 1 PP. P NP 2 Det. the 0 Det. a 1 V. ate 2 Det. a 1 P. with
72 0 Papa 1 ate 2 the 3 caviar 4 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 Det. the 1 PP. P NP 2 Det. the 0 Det. a 1 V. ate 2 Det. a 1 P. with attach
73 0 Papa 1 ate 2 the 3 caviar 4 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 Det. the 1 PP. P NP 2 Det. the 0 Det. a 1 V. ate 2 Det. a 1 P. with attach (again!)
74 0 Papa 1 ate 2 the 3 caviar 4 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 0 Det. a 1 V. ate 2 Det. a 1 P. with attach (again!)
75 0 Papa 1 ate 2 the 3 caviar 4 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 1 P. with
76 0 Papa 1 ate 2 the 3 caviar 4 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 1 P. with 0 ROOT S. attach (again!)
77 0 Papa 1 ate 2 the 3 caviar 4 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 1 P. with 0 ROOT S.
78 0 Papa 1 ate 2 the 3 caviar 4 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 1 P. with 0 ROOT S. 4 P. with
79 0 Papa 1 ate 2 the 3 caviar 4 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 1 P. with 0 ROOT S. 4 P. with
80 0 Papa 1 ate 2 the 3 caviar 4 with 5 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 4 P with. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 1 P. with 0 ROOT S. 4 P. with
81 0 Papa 1 ate 2 the 3 caviar 4 with 5 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 4 P with. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 4 PP P. NP 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 1 P. with 0 ROOT S. 4 P. with
82 0 Papa 1 ate 2 the 3 caviar 4 with 5 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 4 P with. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 4 PP P. NP 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 5 NP. Det N 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP. NP PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 5 NP. Papa 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 1 P. with 0 ROOT S. 4 P. with
83 0 Papa 1 ate 2 the 3 caviar 4 with 5 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 4 P with. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 4 PP P. NP 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 5 NP. Det N 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP. NP PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 5 NP. Papa 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 5 Det. the 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 5 Det. a 1 P. with 0 ROOT S. 4 P. with
84 0 Papa 1 ate 2 the 3 caviar 4 with 5 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 4 P with. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 4 PP P. NP 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 5 NP. Det N 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP. NP PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 5 NP. Papa 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 5 Det. the 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 5 Det. a 1 P. with 0 ROOT S. 4 P. with
85 0 Papa 1 ate 2 the 3 caviar 4 with 5 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 4 P with. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 4 PP P. NP 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 5 NP. Det N 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP. NP PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 5 NP. Papa 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 5 Det. the 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 5 Det. a 1 P. with 0 ROOT S. 4 P. with
86 0 Papa 1 ate 2 the 3 caviar 4 with 5 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 4 P with. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 4 PP P. NP 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 5 NP. Det N 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP. NP PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 5 NP. Papa 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 5 Det. the 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 5 Det. a 1 P. with 0 ROOT S. 4 P. with
87 ate 2 the 3 caviar 4 with 5 a 6. 1 V ate. 2 Det the. 3 N caviar. 4 P with. 5 Det a. 1 VP V. NP 2 NP Det. N 2 NP Det N. 4 PP P. NP P 2 NP. Det N 3 N. caviar 1 VP V NP. 5 NP. Det N 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP. NP PP P 2 NP. Papa 0 S NP VP. 5 NP. Papa 2 Det. the 1 VP VP. PP 5 Det. the 2 Det. a 4 PP. P NP 5 Det. a 0 ROOT S. 4 P. with
88 ate 2 the 3 caviar 4 with 5 a 6. 1 V ate. 2 Det the. 3 N caviar. 4 P with. 5 Det a. 1 VP V. NP 2 NP Det. N 2 NP Det N. 4 PP P. NP 5 NP Det. N P 2 NP. Det N 3 N. caviar 1 VP V NP. 5 NP. Det N 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP. NP PP P 2 NP. Papa 0 S NP VP. 5 NP. Papa 2 Det. the 1 VP VP. PP 5 Det. the 2 Det. a 4 PP. P NP 5 Det. a 0 ROOT S. 4 P. with
89 ate 2 the 3 caviar 4 with 5 a 6. 1 V ate. 2 Det the. 3 N caviar. 4 P with. 5 Det a. 1 VP V. NP 2 NP Det. N 2 NP Det N. 4 PP P. NP 5 NP Det. N P 2 NP. Det N 3 N. caviar 1 VP V NP. 5 NP. Det N 6 N. caviar 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP. NP PP 6 N. spoon P 2 NP. Papa 0 S NP VP. 5 NP. Papa 2 Det. the 1 VP VP. PP 5 Det. the 2 Det. a 4 PP. P NP 5 Det. a 0 ROOT S. 4 P. with
90 ate 2 the 3 caviar 4 with 5 a 6. 1 V ate. 2 Det the. 3 N caviar. 4 P with. 5 Det a. 1 VP V. NP 2 NP Det. N 2 NP Det N. 4 PP P. NP 5 NP Det. N P 2 NP. Det N 3 N. caviar 1 VP V NP. 5 NP. Det N 6 N. caviar 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP. NP PP 6 N. spoon P 2 NP. Papa 0 S NP VP. 5 NP. Papa 2 Det. the 1 VP VP. PP 5 Det. the 2 Det. a 4 PP. P NP 5 Det. a 0 ROOT S. 4 P. with
91 ate 2 the 3 caviar 4 with 5 a 6 spoon 7. 1 V ate. 2 Det the. 3 N caviar. 4 P with. 5 Det a. 6 N spoon. 1 VP V. NP 2 NP Det. N 2 NP Det N. 4 PP P. NP 5 NP Det. N P 2 NP. Det N 3 N. caviar 1 VP V NP. 5 NP. Det N 6 N. caviar 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP. NP PP 6 N. spoon P 2 NP. Papa 0 S NP VP. 5 NP. Papa 2 Det. the 1 VP VP. PP 5 Det. the 2 Det. a 4 PP. P NP 5 Det. a 0 ROOT S. 4 P. with
92 ate 2 the 3 caviar 4 with 5 a 6 spoon 7. 1 V ate. 2 Det the. 3 N caviar. 4 P with. 5 Det a. 6 N spoon. 1 VP V. NP 2 NP Det. N 2 NP Det N. 4 PP P. NP 5 NP Det. N 5 NP Det N. P 2 NP. Det N 3 N. caviar 1 VP V NP. 5 NP. Det N 6 N. caviar 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP. NP PP 6 N. spoon P 2 NP. Papa 0 S NP VP. 5 NP. Papa 2 Det. the 1 VP VP. PP 5 Det. the 2 Det. a 4 PP. P NP 5 Det. a 0 ROOT S. 4 P. with
93 ate 2 the 3 caviar 4 with 5 a 6 spoon 7. 1 V ate. 2 Det the. 3 N caviar. 4 P with. 5 Det a. 6 N spoon. 1 VP V. NP 2 NP Det. N 2 NP Det N. 4 PP P. NP 5 NP Det. N 5 NP Det N. P 2 NP. Det N 3 N. caviar 1 VP V NP. 5 NP. Det N 6 N. caviar 4 PP P NP. 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP. NP PP 6 N. spoon 5 NP NP. PP P 2 NP. Papa 0 S NP VP. 5 NP. Papa 2 Det. the 1 VP VP. PP 5 Det. the 2 Det. a 4 PP. P NP 5 Det. a 0 ROOT S. 4 P. with
94 0 Papa 1 ate 2 the 3 caviar 4 with a spoon 7 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 6 N spoon. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 5 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 4 PP P NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 2 NP NP PP. 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 1 VP VP PP. 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 1 P. with 0 ROOT S. 4 P. with
95 0 Papa 1 ate 2 the 3 caviar 4 with a spoon 7 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 6 N spoon. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 5 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 4 PP P NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 2 NP NP PP. 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 1 VP VP PP. 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 7 PP. P NP 1 P. with 0 ROOT S. 4 P. with
96 0 Papa 1 ate 2 the 3 caviar 4 with a spoon 7 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 6 N spoon. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 5 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 4 PP P NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 2 NP NP PP. 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 1 VP VP PP. 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 7 PP. P NP 1 P. with 0 ROOT S. 1 VP V NP. 4 P. with 2 NP NP. PP
97 0 Papa 1 ate 2 the 3 caviar 4 with a spoon 7 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 6 N spoon. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 5 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 4 PP P NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 2 NP NP PP. 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 1 VP VP PP. 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 7 PP. P NP 1 P. with 0 ROOT S. 1 VP V NP. 4 P. with 2 NP NP. PP 0 S NP VP. 1 VP VP. PP
98 0 Papa 1 ate 2 the 3 caviar 4 with a spoon 7 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 6 N spoon. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 5 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 4 PP P NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 2 NP NP PP. 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 1 VP VP PP. 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 7 PP. P NP 1 P. with 0 ROOT S. 1 VP V NP. 4 P. with 2 NP NP. PP 0 S NP VP. 1 VP VP. PP 7 P. with
99 0 Papa 1 ate 2 the 3 caviar 4 with a spoon 7 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 6 N spoon. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 5 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 4 PP P NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 2 NP NP PP. 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 1 VP VP PP. 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 7 PP. P NP 1 P. with 0 ROOT S. 1 VP V NP. 4 P. with 2 NP NP. PP 0 S NP VP. 1 VP VP. PP 7 P. with
100 0 Papa 1 ate 2 the 3 caviar 4 with a spoon 7 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 6 N spoon. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 5 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 4 PP P NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 2 NP NP PP. 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 1 VP VP PP. 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 7 PP. P NP 1 P. with 0 ROOT S. 1 VP V NP. 4 P. with 2 NP NP. PP 0 S NP VP. 1 VP VP. PP 7 P. with
101 0 Papa 1 ate 2 the 3 caviar 4 with a spoon 7 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 6 N spoon. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 5 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 4 PP P NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 2 NP NP PP. 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 1 VP VP PP. 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 7 PP. P NP 1 P. with 0 ROOT S. 1 VP V NP. 4 P. with 2 NP NP. PP 0 S NP VP. 1 VP VP. PP 7 P. with 0 ROOT S.
102 0 Papa 1 ate 2 the 3 caviar 4 with a spoon 7 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 6 N spoon. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 5 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 4 PP P NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 2 NP NP PP. 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 1 VP VP PP. 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 7 PP. P NP 1 P. with 0 ROOT S. 1 VP V NP. 4 P. with 2 NP NP. PP 0 S NP VP. 1 VP VP. PP 7 P. with 0 ROOT S.
103 0 Papa 1 ate 2 the 3 caviar 4 with a spoon 7 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 6 N spoon. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 5 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 4 PP P NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 2 NP NP PP. 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 1 VP VP PP. 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 7 PP. P NP 1 P. with 0 ROOT S. 1 VP V NP. 4 P. with 2 NP NP. PP 0 S NP VP. 1 VP VP. PP 7 P. with 0 ROOT S.
104 0 Papa 1 ate 2 the 3 caviar 4 with a spoon 7 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 6 N spoon. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 5 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 4 PP P NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 2 NP NP PP. 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 1 VP VP PP. 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 7 PP. P NP 1 P. with 0 ROOT S. 1 VP V NP. 4 P. with 2 NP NP. PP 0 S NP VP. 1 VP VP. PP 7 P. with 0 ROOT S.
105 0 Papa 1 ate 2 the 3 caviar 4 with a spoon 7 0 ROOT. S 0 NP Papa. 1 V ate. 2 Det the. 3 N caviar. 6 N spoon. 0 S. NP VP 0 S NP. VP 1 VP V. NP 2 NP Det. N 2 NP Det N. 5 NP Det N. 0 NP. Det N 0 NP NP. PP 2 NP. Det N 3 N. caviar 1 VP V NP. 4 PP P NP. 0 NP. NP PP 1 VP. V NP 2 NP. NP PP 3 N. spoon 2 NP NP. PP 5 NP NP. PP 0 NP. Papa 1 VP. VP PP 2 NP. Papa 0 S NP VP. 2 NP NP PP. 0 Det. the 1 PP. P NP 2 Det. the 1 VP VP. PP 1 VP VP PP. 0 Det. a 1 V. ate 2 Det. a 4 PP. P NP 7 PP. P NP 1 P. with 0 ROOT S. 1 VP V NP. 4 P. with 2 NP NP. PP 0 S NP VP. 1 VP VP. PP 7 P. with 0 ROOT S.
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