<commit_before>---
layout: base
title:  'Enhanced Dependencies in UD v2'
---

# Enhanced Dependencies in UD v2

The first version of the guidelines provided very little guidance regarding the _enhanced_ representation and so far only very few treebanks contain additional dependencies. For v2, we propose the following guidelines for the _enhanced_ representation:


* We provide guidelines for the following additions:
 * Null nodes for elided predicates
 * Additional subject relations for control and raising constructions
 * Propagation of conjuncts
 * Arguments of passive verbs
 * Relative clauses 
* The _enhanced_ graph is not necessarily a supergraph of the basic tree, i.e., it is not required to contain all the relations of the original
* We leave it up to the treebank maintainers to decide whether and to what extent they want to add relations for the enhanced representation
 

## Ellipsis 

(See also the notes on [ellipsis](ellipsis.html).)

In the _enhanced_ representation, we add special null nodes in clauses in which a predicate is elided.

~~~ sdparse
I like tea and you E5.1 coffee .

nsubj(like-2, I-1)
dobj(like-2, tea-3)
nsubj(E5.1-6, you-5)
conj(like-2, E5.1-6)
dobj(E5.1-6, coffee-7)
~~~ 

~~~ sdparse
Mary wants to buy a book and Jenny E8.1 E8.2 a CD .

nsubj(wants-2, Mary-1)
xcomp(wants-2, buy-4)
dobj(buy-4, book-6)
conj(wants-2, E8.1-9)
nsubj(E8.1-9, Jenny-8)
xcomp(E8.1-9, E8.2-10)<commit_msg>typesetting<commit_after>---
layout: base
title:  'Enhanced Dependencies in UD v2'
---

# Enhanced Dependencies in UD v2

The first version of the guidelines provided very little guidance regarding the _enhanced_ representation and so far only very few treebanks contain additional dependencies. For v2, we propose the following guidelines for the _enhanced_ representation:


* We provide guidelines for the following additions:
    - Null nodes for elided predicates
    - Additional subject relations for control and raising constructions
    - Propagation of conjuncts
    - Arguments of passive verbs
    - Relative clauses 
* The _enhanced_ graph is not necessarily a supergraph of the basic tree, i.e., it is not required to contain all the relations of the original
* We leave it up to the treebank maintainers to decide whether and to what extent they want to add relations for the enhanced representation
 

## Ellipsis 

(See also the notes on [ellipsis](ellipsis.html).)

In the _enhanced_ representation, we add special null nodes in clauses in which a predicate is elided.

~~~ sdparse
I like tea and you E5.1 coffee .

nsubj(like-2, I-1)
dobj(like-2, tea-3)
nsubj(E5.1-6, you-5)
conj(like-2, E5.1-6)
dobj(E5.1-6, coffee-7)
~~~ 

~~~ sdparse
Mary wants to buy a book and Jenny E8.1 E8.2 a CD .

nsubj(wants-2, Mary-1)
xcomp(wants-2, buy-4)
dobj(buy-4, book-6)
conj(wants-2, E8.1-9)
nsubj(E8.1-9, Jenny-8)
xcomp(E8.1-9, E8.2-10)
{'fraction_non_alphanumeric': 0.08225862669919833, 'fraction_numerical': 0.03206692227256884, 'mean_word_length': 3.991304347826087, 'pattern_counts': {'":': 0, '<': 3, '<?xml version=': 0, '>': 3, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
{'dir': 'git-commits-cleaned', 'id': '7466875', 'n_tokens_mistral': 974, 'n_tokens_neox': 917, 'n_words': 387}