Natural language processing Cohesion and Coherence download these

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Natural language processing Cohesion and Coherence download these slides from the google drive. The

Natural language processing Cohesion and Coherence download these slides from the google drive. The link is provided in the docx file.

What is Cohesion & Coherence? Ø Cohesion refers to connectivity in a text. Coherence

What is Cohesion & Coherence? Ø Cohesion refers to connectivity in a text. Coherence refers to how easy it is to understand the writing. Friday, May 21, 2021 Department of Computer Science, University of Peshawar 2

Coherence and cohesion Ø Coherence is defined as the quality of being logical, consistent

Coherence and cohesion Ø Coherence is defined as the quality of being logical, consistent and able to be understood. v Imagine Ø coherence as a building. Cohesion on the other hand refers to the act of forming a whole unit. It is effectively a subset of coherence. v Picture cohesion as the bricks and cement which make up the building. 21 May 2021 3

Cohesion-Definition The action or fact of forming a united whole. Ø Cohesion means sticking

Cohesion-Definition The action or fact of forming a united whole. Ø Cohesion means sticking together. Ø The act or state of sticking together tightly Ø Cohesion is the grammatical and lexical relationship within a text or sentence and can be defined as the links that holds a text together and gives it meaning. Ø v Example: ü Ahmad belongs to Peshawar. He is in M. Sc final year Friday, May 21, 2021 Department of Computer Science, University of Peshawar 4

Coherence-Definition A quality of sentences, paragraphs, and essays when all parts are clearly connected.

Coherence-Definition A quality of sentences, paragraphs, and essays when all parts are clearly connected. v When sentences, ideas, and details fit together clearly, readers can follow along easily, and the writing is coherent. v Cohesion refers to connectivity in a text. Coherence refers to how easy it is to understand the writing. v Coherence provide flow to the discourse units Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 5

Coherence-Examples Ø Ø Example 1: v There once was a farmer in a small

Coherence-Examples Ø Ø Example 1: v There once was a farmer in a small village. He worked hard day and night in his fields to fed his wife and children. Example 2: v Ali is very studious and got 900 marks. His percentage is 92. 1%. Friday, May 21, 2021 Ø Ø Example 1: v There once was a farmer in a small village. He worked hard day and he was digging up sand on the moon. Example 2: v Ali is a studious and got a laptop which he always uses during dinner. Department of Computer Science, University of Peshawar 6

Example-poor connectivity The hotel is famous. It is one of the most wellknown hotels

Example-poor connectivity The hotel is famous. It is one of the most wellknown hotels in the country. The latest international dancing competition was held at the hotel. The hotel spent a lot of money to advertise the event. Because the hotel wanted to gain international reputation. But not many people attended the event. Ø (The connection of ideas is not very good. ) Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 7

Example – better relation The hotel, which is one of the most wellknown hotels

Example – better relation The hotel, which is one of the most wellknown hotels in this region, wanted to promote its image around the world by hosting the latest international dancing competition. Although the event was widely advertised, not many people participated in the competition. Ø (The connection of ideas is better than in the first example. ) Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 8

Example-better than first example The latest international dancing competition was held at the hotel,

Example-better than first example The latest international dancing competition was held at the hotel, which is one of the most well-known hotels in this region. The hotel spent a lot of money on advertising the event since it wanted to enhance its international reputation; however, it failed to attract many people. Ø (The connection of ideas is better than in the first example achieving coherence and cohesion) Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 9

Why coherence? Ø Ø Ø The text-based features, which provide cohesion in a text

Why coherence? Ø Ø Ø The text-based features, which provide cohesion in a text do not necessarily help achieve coherence (simply put cohesion is not enough) That is, they do not always contribute to the meaningfulness of a text, be it written or spoken. It has been stated that a text coheres* only if the world around is also coherent. * Forms a unified whole, be logically consistent Friday, May 21, 2021 Department of Computer Science, University of Peshawar 10

Cohesion or coherence OR both? Ø Ø Ø Can you have cohesion without coherence?

Cohesion or coherence OR both? Ø Ø Ø Can you have cohesion without coherence? Can you have coherence without cohesion? You can have cohesion without coherence but you cannot have coherence without cohesion. v The picture does not make sense unless the correct pieces are placed in the correct order, even if certain pieces may be the same size and shape. v Example: I bought some hummus to eat with celery. Green vegetables can boost your metabolism. The Australian Greens is a political party. I couldn’t decide what to wear to the new year’s party. Friday, May 21, 2021 Department of Computer Science, University of Peshawar 11

Cohesive devices Ø Now discussion is going to be about cohesion and related concepts.

Cohesive devices Ø Now discussion is going to be about cohesion and related concepts. Ø Definition: v The links within the text that hold it together are called cohesive devices. Friday, May 21, 2021 Department of Computer Science, University of Peshawar 12

Categories of cohesive devices Ø A cohesive text is created in many different ways.

Categories of cohesive devices Ø A cohesive text is created in many different ways. In Cohesion in English, M. A. K. Halliday and Ruqaiya Hasan (1976) identify five general categories of cohesive devices that create coherence in texts: 1. 2. 3. 4. 5. Ø Reference, Ellipsis, Substitution, Conjunction, Lexical cohesion. Ref Grammatical cohesion http: //www. criticism. com/da/coherence. php Friday, May 21, 2021 Department of Computer Science, University of Peshawar 13

1. References or referring expressions Ø A natural language expression used to perform reference

1. References or referring expressions Ø A natural language expression used to perform reference is called a referring expression and the entity that is referred to is called the referent. Ø Example: v A pretty woman entered the restaurant. She sat at the table next to mine and only then I recognized her. This was Amy Garcia, my next door neighbor from 10 years ago. The woman has totally changed! Amy was at the time shy… Friday, May 21, 2021 Department of Computer Science, University of Peshawar 14

Types of References Personal (communication goal of referent ) Ø Demonstrative (Proximity of referent

Types of References Personal (communication goal of referent ) Ø Demonstrative (Proximity of referent ) Ø Comparative (similarity to preceding referent) Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 15

i. Personal Reference A reference by means of person Ø Includes Ø v Personal

i. Personal Reference A reference by means of person Ø Includes Ø v Personal pronouns (e. g. I, he, she, its) v Possessive pronouns (e. g. mine, hers, his) v Possessive determiners (e. g. my, your, her) E. g. English is considered an international language. It is spoken by more than 260 million people all over the world. Ø They told me that you had gone by her car. Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 16

i-a. Personal pronoun Examples: If the buyer wants to look the condition of the

i-a. Personal pronoun Examples: If the buyer wants to look the condition of the property he has to have another survey. One carried out on his own behalf. Ø Here in the above example the use of personal pronoun ‘he’ or ‘his’ for ‘buyer’ and ‘one’ for ‘survey’ is a source of personal reference. Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 17

i-b. Possessive pronoun If possessive pronouns are used, they give two more notions other

i-b. Possessive pronoun If possessive pronouns are used, they give two more notions other than speaker and addressee. They are that of ‘possessor’ and ‘possessed’ Example: That new house is John’s. I didn’t know it was his. Ø Here, in the above example the use of possessive pronouns ‘his’ for ‘John’ indicates the possessor and ‘’s’ is for the possessed ‘house’ includes another source of personal reference. Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 18

i-c. Possessive determinant Ø Example: John’s house is beautiful. His wife must be delighted

i-c. Possessive determinant Ø Example: John’s house is beautiful. His wife must be delighted with it. Ø Here, in this example the use of the possessive determiner ‘his’ for ‘John’ is who a source of personal reference. Friday, May 21, 2021 Department of Computer Science, University of Peshawar 19

Possessive pronounce vs determiner Possessive pronouns indicate possession or belonging. Ø Possessive determiners, also

Possessive pronounce vs determiner Possessive pronouns indicate possession or belonging. Ø Possessive determiners, also called possessive adjectives (my/your etc. ), come before a noun. Ø whereas, possessive pronouns (mine/yours etc. ) replace a noun. Ø Ø Example: My name’s Polly and I’m looking for my hat. My dad says there’s one in the wardrobe, but it’s his, not mine. My mum has also got a hat. Look! The dog’s wearing hers. Friday, May 21, 2021 Department of Computer Science, University of Peshawar 20

Types of References Ø Personal (communication goal of referent ) v Personal pronouns (e.

Types of References Ø Personal (communication goal of referent ) v Personal pronouns (e. g. I, he, she, its) v Possessive pronouns (e. g. mine, hers, his) v Possessive determiners (e. g. my, your, her) Demonstrative (Proximity of referent ) Ø Comparative (similarity to preceding referent) Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 21

ii. Demonstrative Reference Essentially a form of verbal pointing Ø The speaker identifies the

ii. Demonstrative Reference Essentially a form of verbal pointing Ø The speaker identifies the referent by locating it on a scale of proximity Ø In general Ø v This , these , here imply proximity to the speaker v That, those, there imply distance from the speaker v E. g. How do you like cruise in that yacht? v Pick these up Friday, May 21, 2021 Department of Computer Science, University of Peshawar 22

Examples of demonstrative reference: Leave that there and come here Ø Where do you

Examples of demonstrative reference: Leave that there and come here Ø Where do you come from? Ø I like the lions and I like the Polar bears. – (neutral) Ø These are my favourites and those are too. Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 23

Types of References Ø Personal (communication goal of referent ) v Personal pronouns (e.

Types of References Ø Personal (communication goal of referent ) v Personal pronouns (e. g. I, he, she, its) v Possessive pronouns (e. g. mine, hers, his) v Possessive determiners (e. g. my, your, her) Demonstrative (Proximity of referent ) Ø Comparative (similarity to preceding referent) Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 24

iii. Comparative Reference Comparative reference is indirect reference by means of IDENTITY or SIMILARITY.

iii. Comparative Reference Comparative reference is indirect reference by means of IDENTITY or SIMILARITY. Ø Here two types of comparison are given. Ø v General comparison v Particular comparison Friday, May 21, 2021 Department of Computer Science, University of Peshawar 25

iii-a. General comparison: By ‘general comparison’ is meant comparison that is simply in terms

iii-a. General comparison: By ‘general comparison’ is meant comparison that is simply in terms of likeness and unlikeness without considering any particular property: Ø two things may be the same, similar or different, general comparison is expressed by a certain class of adjectives and adverbs Ø Example: Ø It’s the same cat as the one we saw yesterday. Ø Its different cat from the one we saw yesterday. Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 26

iii-b. Particular comparison: Particular comparison means comparison that is in respect of quantity or

iii-b. Particular comparison: Particular comparison means comparison that is in respect of quantity or quality. Ø Example: Ø We are demanding higher living standard. Ø There are twice as many people there as the last time. Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 27

Types of References Ø Personal (communication goal of referent ) v Personal pronouns (e.

Types of References Ø Personal (communication goal of referent ) v Personal pronouns (e. g. I, he, she, its) v Possessive pronouns (e. g. mine, hers, his) v Possessive determiners (e. g. my, your, her) Ø Demonstrative (Proximity of referent ) v This, Ø there, that Comparative (similarity to preceding referent) v General comparison v Particular comparison Friday, May 21, 2021 v Department of Computer Science, University of Peshawar 28

References general Example A pretty woman entered the restaurant. She sat at the table

References general Example A pretty woman entered the restaurant. She sat at the table next to mine and only then, I recognized her. This was Amy Garcia, my next door neighbor from 10 years ago. The woman has totally changed! Amy was at the time shy… Referent Anaphoric Referring Expression Friday, May 21, 2021 Department of Computer Science, University of Peshawar Cataporic Referring Expression 29

i. Exophoric reference Ø Ø Exophoric reference, depends on the context outside the text

i. Exophoric reference Ø Ø Exophoric reference, depends on the context outside the text for its meaning. In linguistics, Exophora is reference to something extralinguistic i. e. , not in the same text. v Ø Ø Exophora = extra linguistic pronouns with words such as ‘this’ ‘that’ ‘there’ ‘here’ are often exophoric. For example v "What is this? ", ü here "this" is exophoric rather than endophoric, because it refers to something extra-linguistic, i. e. there is not enough information in the utterance itself to determine what "this" refers to, but we must instead observe the non-linguistic context of the utterance (e. g. the speaker might be holding an unknown object in their hand as they ask that question. ) Friday, May 21, 2021 Department of Computer Science, University of Peshawar 30

Examples-Exophora Ø Did the gardener water those plants? v Ø It is quite possible

Examples-Exophora Ø Did the gardener water those plants? v Ø It is quite possible that ‘those’ refers to earlier mention of those particular plants in the discussion. But it is also possible that it refers to the environment in which the dialogue is taking place For he’s a jolly good fellow and so say all of us. v This is an example of the context of situation where the text is not indicating who this ‘he’ is. Friday, May 21, 2021 Department of Computer Science, University of Peshawar 31

Homophoric reference is where the identity of the item can be retrieved by reference

Homophoric reference is where the identity of the item can be retrieved by reference to cultural knowledge, in general, rather than specific context of the text. Ø Homophoric reference occurs when a generic phrase obtains a specific meaning through knowledge of its context. Ø v For example, the meaning of the phrase “the Queen” may be determined by the country in which it is spoken. Friday, May 21, 2021 Department of Computer Science, University of Peshawar 32

ii. Endophoric Reference Ø Ø The pronouns refer to items within the same text;

ii. Endophoric Reference Ø Ø The pronouns refer to items within the same text; it is endophoric reference. Endophora is a linguistic reference to something intralinguistic in the same text. v Endophora = intra-linguistic v For v Example: "I saw Sally yesterday, she was going to the mall". ü Here, "she" is intra-linguistic, and hence endophoric, because it refers to something (Sally, in this case) already mentioned in the text. ¨ (From Wikipedia, the free encyclopedia) Friday, May 21, 2021 Department of Computer Science, University of Peshawar 33

Endophora (Another Definition) Ø Words or phrases like pronouns are endophora when they point

Endophora (Another Definition) Ø Words or phrases like pronouns are endophora when they point backwards or forwards to something in the text: v For example: ü As [he]1 was late, [Harry] 1 wanted to phone [his] [boss] 2 and tell [her] 2 what had happened. ¨ 1 (From Wikipedia, the free encyclopedia) Friday, May 21, 2021 Department of Computer Science, University of Peshawar 34

Types of Endophora Ø 1) Cataphora (forward referencing) v The type of endophora in

Types of Endophora Ø 1) Cataphora (forward referencing) v The type of endophora in which the referring expression occur before the referent are termed as cataphora. v OR The type of endophora in which the pronouns link forward to a referent (nouns) in the text that follows. v For example: ü When [she] 1 saw the snake, [Harry] 1 cried. ü The elevator opened for [him] 1 on the 14 th flour, and [Ali] 1 stepped out quickly. Friday, May 21, 2021 Department of Computer Science, University of Peshawar 35

Types of Endophora Ø 2) Anaphora (Backward Referencing): The type of endophora in which

Types of Endophora Ø 2) Anaphora (Backward Referencing): The type of endophora in which the referent occurs before the referring expression are termed as anaphora. v OR The type of endophora in which the pronouns link backward to a referent (nouns) in the text. v Ø For Example: 1)John helped Mary. v 2) He was kind. v Referring Element/ Anaphoric Device (AD) Friday, May 21, 2021 Correlate/ Referent/ Antecedent Department of Computer Science, University of Peshawar 36

Examples of Anaphora Marry invited Susan for a visit and she gave her a

Examples of Anaphora Marry invited Susan for a visit and she gave her a good lunch. She = Marry her = Susan Ø On the train to Boston, George chatted with another passenger. The man turned out to be a professional hockey player. Ø The man = Another passenger Ø Bill told Amy that he will spend his vacation in London next year. He= Bill Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 37

Anaphoric and Cataphoric Devices Ø The referring elements (pronouns) in anaphoric text that refer

Anaphoric and Cataphoric Devices Ø The referring elements (pronouns) in anaphoric text that refer to their corresponding referent ( nouns) backward are called anaphoric devices. Also, called anaphor. v For example: ü Bell is a powerful player but unfortunately he will not take part in the trophy due to injury. Anaphoric Device Ø The referring elements (pronouns) that refer to their corresponding referent (nouns) forward in cataphoric text are called cataphoric devices. Also, called cataphor. v For example: ü As her father went abroad, Nighat took control of the organization by herself. Cataphoric Device Friday, May 21, 2021 Department of Computer Science, University of Peshawar 38

Antecedent Ø The referent in the anaphoric/cataphoric text to which the anaphoric/cataphoric devices refer

Antecedent Ø The referent in the anaphoric/cataphoric text to which the anaphoric/cataphoric devices refer are called Ø Also, called correlates v For ü antecedents. . example: Bell is a powerful player but unfortunately he will not take part in the trophy due to injury. Antecedent ü As her father went abroad, Nighat took control of the organization by herself. Friday, May 21, 2021 Department of Computer Science, University of Peshawar 39

Types of Anaphora (On the basis of position of anaphor and its antecedent) Ø

Types of Anaphora (On the basis of position of anaphor and its antecedent) Ø Intra-sentential/Sentence internal anaphora: The anaphora in which the AD and its antecedent both occurs in the same sentence is called sentence internal. v Reflexive pronouns v ü v Possessive pronouns ü v (himself, herself, itself, themselves) are typical examples of intrasentential anaphora. (his, hers, its, theirs) can often be used as intra-sentential anaphors too, and often be in the same clause as the anaphor. For example: ü [John] 1 took [his] 1 [hat] 2 off and hung [it]2 on a peg. Friday, May 21, 2021 Department of Computer Science, University of Peshawar 40

Types of Anaphora (Cont. . ) Ø Inter-sentential/Sentence external anaphora: v The anaphora in

Types of Anaphora (Cont. . ) Ø Inter-sentential/Sentence external anaphora: v The anaphora in which the AD and its antecedent doesn’t occur in the same sentence is called sentence external or inter-sentential anaphora. v For example: ü ü [Jehansher] 1 Khan was senior player of Sqash. [He] 1 has won several trophies. [John] 1 took his hat off and hung it on a peg. [He] 1 was very tired therefore he went to slept. Friday, May 21, 2021 Department of Computer Science, University of Peshawar 41

Anaphora and ambiguity Ø Many anaphors are ambiguous. Like: v A) Jane told Marry

Anaphora and ambiguity Ø Many anaphors are ambiguous. Like: v A) Jane told Marry that she may get hurt. (ambiguous) ü Jane informed Marry she may get hurt. (Here Jane may hurt) ü v B) Jane told Marry she was in danger (ambiguous) ü Jane warned Marry she was in danger. ü Friday, May 21, 2021 Department of Computer Science, University of Peshawar 42

Anaphora Resolution Ø Ø Anaphora Resolution == the problem of resolving what a pronoun,

Anaphora Resolution Ø Ø Anaphora Resolution == the problem of resolving what a pronoun, or a noun phrase refers to. Consider the following Discourse: 1) John helped Mary. 2) He was kind. Ø After anaphora resolution: 1) John helped Mary. 2) John was kind. Friday, May 21, 2021 Department of Computer Science, University of Peshawar 43

2. Ellipsis Ø Definition: v The omission of a portion, of a phrase or

2. Ellipsis Ø Definition: v The omission of a portion, of a phrase or a sentence is called Ellipsis. v Example: He is rich, but his brother is not. ü Bob was born in London and Amy in Paris. ü I am allergic to tomatoes. Also fish. ü Bob and Tom ate cheese. ü Friday, May 21, 2021 Department of Computer Science, University of Peshawar 44

Other examples Ø George bought a huge box of chocolates but few Ǿ were

Other examples Ø George bought a huge box of chocolates but few Ǿ were left by the end of the day. Chocolates Ø I have never been to Karachi but my father had Ǿ , and he says it was wonderful. Been to Karachi Friday, May 21, 2021 Department of Computer Science, University of Peshawar 45

Origin of the word ellipsis Derived from Greek, the word 'ellipsis' means “the omission

Origin of the word ellipsis Derived from Greek, the word 'ellipsis' means “the omission of words that could be understood from the context”. Ø Ellipsis is the non-expression of one or more sentence elements whose meaning can be reconstructed either from the context or from a person’s knowledge of the world. Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 46

e-clause & a-clause Ø e-clause: The clause from which the material is missing is

e-clause & a-clause Ø e-clause: The clause from which the material is missing is often referred to as the elliptical clause (e-clause). v Example: v ü Ø ᶲ He is rich, but his brother is not. a-clause: The clause from which the interpretation of the missing material is derived is referred to as antecedent clause (aclause). v Example: v ü ᶲ He is rich, but his brother is not. Friday, May 21, 2021 Department of Computer Science, University of Peshawar 47

Ellipsis resolution Ellipses resolution is an important area in the research community. Ø All

Ellipsis resolution Ellipses resolution is an important area in the research community. Ø All natural languages have the occurrences of ellipses in their text as well as speech, although different from each other. Ø For their resolution different approaches are followed by linguists as described by Shalom Lappin (Lappin and Lease). Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 48

Examples of ellipsis resolution Ø Ø Ø He is rich, but his brother is

Examples of ellipsis resolution Ø Ø Ø He is rich, but his brother is not ᶲ. (= He is rich but his brother is not rich). Bob ᶲ and Tom ate cheese. (= Bob (ate cheese) and Tom ate cheese). John realizes that he is a fool, but Bill does not ᶲ, even though his wife does ᶲ. (= John realizes that John is a fool, but Bill does not realize that Bill is a fool, even though Bill's wife realizes that Bill is a fool. ) Friday, May 21, 2021 Department of Computer Science, University of Peshawar 49

Examples Ø Ø Ø John can play the guitar, and Mary can play the

Examples Ø Ø Ø John can play the guitar, and Mary can play the violin. Fred took a picture of you, and Susan took a picture of me. She persuaded him to do the homework, and he persuaded her to do the homework. Should I call you, or should you call me? John can play the guitar, and Mary can play the guitar, too. Sam has attempted problem 1 twice, and he has attempted problem 2 also. Friday, May 21, 2021 Department of Computer Science, University of Peshawar 50

Sam did it, not Fred did it. Ø Sally is working on Monday, she

Sam did it, not Fred did it. Ø Sally is working on Monday, she is working not on Tuesday. Ø They have been eating the apples more than they have been eating the oranges. Ø I will feed the chickens today if you willfeed the chickens tomorrow. Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 51

Q/A Ellipses Q: Who has been hiding the truth? A: Billy has been hiding

Q/A Ellipses Q: Who has been hiding the truth? A: Billy has been hiding the truth. Ø Q: What have you been trying to accomplish? A: I have been trying to accomplish This damn crossword. Ø Q: When does the circus start? A: The circus starts Tomorrow. Ø Q: Why has the campaign been so crazy? A: The campaign has been so crazy Due to the personalities. Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 52

John can play something, but I don’t know what he can play. Ø When

John can play something, but I don’t know what he can play. Ø When he will call I don't know, but John will definitely call. Ø More people arrived than we expected people would arrive. Ø She ordered more tea than we could drink tea. Ø Doris looks more satisfied than Doreen looks satisfied. Ø William has friends in more countries than you have friends in countries. Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 53

3. Substitution Ø Ø Ø Substitution is very similar to ellipsis in the sense

3. Substitution Ø Ø Ø Substitution is very similar to ellipsis in the sense that it occurs when instead of leaving out a word or a phrase (as in ellipsis), it is substituted for another, more general word. It is a relation in the wording rather than in the meaning. As a process within the text, substitution functions as the replacement of one item by another Friday, May 21, 2021 Department of Computer Science, University of Peshawar 54

Examples "Which ice-cream would you like? “ "I would like the pink one" v"one"

Examples "Which ice-cream would you like? “ "I would like the pink one" v"one" is used instead of repeating "ice -cream. " Ø "When I quote others I do so in order to express my own ideas more clearly. ” Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 55

Examples (2) I bet you will get graduated [A] before I get graduated [A].

Examples (2) I bet you will get graduated [A] before I get graduated [A]. - repetition I bet you will get graduated [A] before I do [B]. - substitution, using do as a substitute for get graduated” Ø The flower seller cries, “Red flowers, red flowers, come and buy ones and present her”. Ø Here, ones substitutes for red flowers. Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 56

Examples(3) My axe is too blunt. I must get a sharper one. Ø You

Examples(3) My axe is too blunt. I must get a sharper one. Ø You think Joan already knows? I think everybody does. Ø v Here, one and does are both substitutes; one for axe and does for knows. Friday, May 21, 2021 Department of Computer Science, University of Peshawar 57

Types of Substitution: Nominal Substitution Ø Verbal Substitution Ø Clausal Substitution Ø Friday, May

Types of Substitution: Nominal Substitution Ø Verbal Substitution Ø Clausal Substitution Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 58

i. Nominal Substitution Nominal substitution means the replacement of a noun or a noun

i. Nominal Substitution Nominal substitution means the replacement of a noun or a noun phrase by a nominal substitute, i. e. – one/ ones, same. Ø Example – Ø a. Have you any knives? I need a sharp one. Ø b. He studied the whole text last night. I did the same. Ø Ø Here, in example a, one for ‘knives’ functions as the head of the noun whereas ‘the whole text last night’ is replaced by same. Friday, May 21, 2021 Department of Computer Science, University of Peshawar 59

Examples: Nominal Substitution Cherry ripe, cherry ripe, ripe I cry, Full and fair ones,

Examples: Nominal Substitution Cherry ripe, cherry ripe, ripe I cry, Full and fair ones, come and buy. Ø I’ll have two poached eggs on toast, please. I’ll do the same. Or just “the same please”. Ø They all started shouting, so I did the same. Ø Charles is now an actor. Given half a chance I would have been the same. Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 60

ii. Verbal Substitution The verbal substitution in English is ‘do’. Ø Example – Ø

ii. Verbal Substitution The verbal substitution in English is ‘do’. Ø Example – Ø ‘I don’t know the meaning of half those long words, and, what’s more, I don’t believe you do either!’ Ø Do substitutes for know the meaning of half those long words. Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 61

iii. Clausal Substitution There is one further type of substitution in which what is

iii. Clausal Substitution There is one further type of substitution in which what is presupposed is not an element within the clause but an entire clause. The words used as clausal substitutes are ‘so’ and ‘not’. Ø Is there going to be an earthquake? / It says so. Ø Here, the ‘so’ presupposes the whole of the clause ‘there is going to be an earthquake Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 62

Examples As for ‘so’: They have failed, then? /I regret so. Ø As for

Examples As for ‘so’: They have failed, then? /I regret so. Ø As for ‘not’: Has everyone gone home? / I hope not. Ø Everyone seems to think he’s guilty. If so, no doubt he will offer to resign. ” Ø Friday, May 21, 2021 Department of Computer Science, University of Peshawar 63

Difference between Reference and Substitution Ø Ø References can reach back a long way

Difference between Reference and Substitution Ø Ø References can reach back a long way in the text. While substitution is usually limited to the immediate preceding clause Another key difference is that with reference there is a typical meaning of co-reference. That is, both items typically refer to the same thing. With ellipsis and substitution, this is not the case. There is always some difference between the second instance and the first. If a speaker or writer wants to refer to the same thing they use reference. If they want to refer to something different they use ellipsis-substitution (Halliday 1985). " Friday, May 21, 2021 Department of Computer Science, University of Peshawar 64

4. Conjunction Ø Conjunction v Conjunction creates cohesion by relating sentences and paragraphs to

4. Conjunction Ø Conjunction v Conjunction creates cohesion by relating sentences and paragraphs to each other by using words from the class of conjunction, or numerals. v This can be: ü ü ü temporal (after, before), causal (because), coordinating (and), adversative (but, however), additive (further) or discourse markers (now, well, after all). Friday, May 21, 2021 Department of Computer Science, University of Peshawar 65

Example (FANBOYS) Ø Ø Ø Ø For presents rationale ("They do not gamble or

Example (FANBOYS) Ø Ø Ø Ø For presents rationale ("They do not gamble or smoke, for they are ascetics. ") And presents non-contrasting item(s) or idea(s) ("They gamble, and they smoke. ") Nor presents a non-contrasting negative idea ("They do not gamble, nor do they smoke. ") But presents a contrast or exception ("They gamble, but they don't smoke. ") Or presents an alternative item or idea ("Every day they gamble, or they smoke. ") Yet presents a contrast or exception ("They gamble, yet they don't smoke. ") So presents a consequence ("He gambled well last night, so he smoked a cigar to celebrate. ") Friday, May 21, 2021 Department of Computer Science, University of Peshawar 66

5. Lexical cohesion Ø Lexical Cohesion v Lexical cohesion is basically created by repetition

5. Lexical cohesion Ø Lexical Cohesion v Lexical cohesion is basically created by repetition (reiteration) of the same lexeme, or general (aka shell) nouns, or other lexemes sharing the majority of semantic features: v The lexical ties can occur over long passages of text or discourse. v For example, ü 'it', 'neither' and 'this' ¨ ü 'First of all', 'then' and 'after that' ¨ ü all refer to an idea previously mentioned. help to sequence a text. 'However', 'in addition' and 'for instance' ¨ link ideas and arguments in a text. Friday, May 21, 2021 Department of Computer Science, University of Peshawar 67

Cohesion vs coherence Ø Difference 1: v Coherent: ü v Cohesion: ü Ø The

Cohesion vs coherence Ø Difference 1: v Coherent: ü v Cohesion: ü Ø The grammatical and lexical relationships between the different elements of the text in a discourse. Difference 2: v Coherence: ü v Coherence is a super set which means that if a text is coherent then it will also be cohesive but the converse is not true Cohesion: ü Ø The semantic relationships which link the meanings of utterances in a discourse. It is a sub set of coherence which means that if a text is cohesive then it may or may not be coherent. Difference 3: v Coherence: ü v The relationship among the parts of the text and sentences is strong. Cohesion: ü The relationship among the parts of the text and sentences is casual. Friday, May 21, 2021 Department of Computer Science, University of Peshawar 68

Bibliography Ø Daniel Jurafsky, Speech and Language Processing: An Introduction to Natural Language Processing,

Bibliography Ø Daniel Jurafsky, Speech and Language Processing: An Introduction to Natural Language Processing, Computational Linguistics and Speech Recognition, Pearson Education, Inc, 1999, Chapter No. 18. Ø Halliday, M. A. K; and Ruqayia Hasan (1976): Cohesion in English. London: Longman. Ø Rav, L. , F. “The Understanding and Generation of Ellipsis in a Natural Language System”, Berkeley AI Research Project Comp: Sc Division University of California Berkeley California. Ø M. A. Khan, “ Text Based Machine Translation System”, Ph. D Thesis, 1995. Ø Lappin, S. , “A Sequenced Model of Anaphora and Ellipsis Resolution”, 2003 Friday, May 21, 2021 Department of Computer Science, University of Peshawar . 69