Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us...
-
Upload
shreya-kerr -
Category
Documents
-
view
218 -
download
2
Transcript of Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us...
![Page 1: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/1.jpg)
Morphology
Dr. Radhika Mamidi
![Page 2: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/2.jpg)
Why are we studying morphology? The knowledge of words will help us
process language computationally at word level.
Knowledge of words include word structure and word formation rules.
This knowledge will help us in developing tools like “Morphological Analyzers” and “Morphological Generators”.
![Page 3: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/3.jpg)
What’s Morphology?
The study of word structure The study of the mental dictionary:
How are words stored in the mind? What is a possible word?
Example:(i) At the supermarket, the girls bought pink cheeriots and the boys blue fistings.
(ii) When their mother signaled, the girls barried home unhappily.
![Page 4: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/4.jpg)
The words ‘fistings’ and ‘barried’ do not exist. However, assuming they are valid words of English, we ‘guess’ the meaning by context and the position of the word in the given sentence. We do this using our general knowledge and linguistic knowledge.
![Page 5: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/5.jpg)
What do you know of cheeriots and fistings?
Part of speech = nouns [comes after adjectives][-s ending]= more than oneMeaning= some objects that have color[clue: supermarket]= some object that is sold; perhaps a toyThe word forms are more like toys, balls,
ribbons.
![Page 6: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/6.jpg)
What do you know of barried
Part of Speech = verb [position]
[ends in –ed]= past tense
Base form= barry
Meaning= go
The word form is more like carried, married.
![Page 7: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/7.jpg)
What’s the Longest Word of English?
Could it be ismestablishmentariandisanti ? Why not when antidisestablishmentarianism is
possible. There is a systematic way of word formation. Possible words:
anti-missile (adjective) anti-missile missile: a missile used for anti-missile
purposes anti- anti-missile missile missile: a missile used
against anti-missile missiles antiNmissileN+1, where N can go until….
![Page 8: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/8.jpg)
Morphemes
Have a sound [form] and a meaning:Example: “cats”
/kaet/ “four-legged animal” /-s/ “plural number”
Even though /-s/ has a sound and a meaning, it can’t mean “plural” by itself…
It has to attach to a noun
![Page 9: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/9.jpg)
“A morpheme is the smallest unit of wordform that has meaning”
Examples:
cats = cat + -s
girlish = girl + -ish
unfriendly = un- + friend + -ly
cat, -s, girl, -ish, un-, friend, -ly are morphemes
![Page 10: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/10.jpg)
Even Bush knows morphology
(…though he may use it differently than the rest of us) The war on terrorism has transformationed
the US-Russia Relationship We’re working to help Russia securitize the
dismantled warheads The explorationists are only willing to help
move equipment during the winter This case has had full analyzation and has
been looked at a lot
![Page 11: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/11.jpg)
Compositionality
“Explorationists” explore: to spend an extended effort looking
around a particular area -ation: can attach to Verbs, the process of
Xing -ist: can attach to Nouns, one who performs
an action Y -s: attaches to Nouns, more than one Z explorationists: a compositional word Fully compositional meaning is based on its
parts
![Page 12: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/12.jpg)
Non-compositionality
“Inflect” Is inflect morphologically complex? It contains more than one morpheme. What do in- and flect mean? This is a case of a non-compositional
meaning. In explorationists, if you know the meaning of the parts, you know the meaning of the whole. Not necessarily so for inflect.
Non-compositional meaning cannot be derived from its parts.
![Page 13: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/13.jpg)
Lexical/Content words
Words which are not function words are called content words or lexical words: these include nouns, verbs, adjectives, and most adverbs, though some adverbs are function words (e.g. then, why).
They belong to open class. Dictionaries define the specific meanings of
content words, but can only describe the general usages of function words.
By contrast, grammars describe the use of function words in detail, but have little interest in lexical words.
![Page 14: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/14.jpg)
Function words
Function words or grammatical words are words that have little lexical meaning or have ambiguous meaning, but instead serve to express grammatical relationships with other words within a sentence.
Function words may be prepositions, pronouns, auxiliary verbs, conjunctions, grammatical articles or particles, all of which belong to the group of closed class words.
![Page 15: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/15.jpg)
To know about morpheme we should know about…. Free morphemes vs. Bound morphemes Lexical morphemes vs. Functional
morphemes Null/Zero morpheme Inflectional morphemes vs. Derivational
morphemes Root morphemes vs. Affix morphemes
![Page 16: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/16.jpg)
Free vs Bound morphemes
electr- and tox- have isolable meanings in electric, electrify, toxic, (de-)toxify
But they cannot be pronounced on their own: they are bound morphemes
girl and book have isolable meanings in girls, girlish, books, booked, booking
They can occur on their own: they are free morphemes
Are prefixes and suffixes bound morphemes?
![Page 17: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/17.jpg)
Lexical morpheme
Lexical free morphemes
apple, smart, book, slow, eat, write, morning
They can exist on their own as independent words.
Lexical bound morphemes: -ceive, -ject, cran-, -ship, un-
They cannot be used independently.
They need another morpheme [free or bound] to form a word.
Eg: re-ceive, con-ceive, sub-ject, pro-ject, cran-berry, scholar-ship, fellow-ship, un-kind, happi-ness
![Page 18: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/18.jpg)
Functional morphemes
Functional free morphemes:
of, with, she, it, and, although, however, because, then
Functional bound morphemes:
-s, -s, -ed, -en, -ing
cats, eats, played, eaten, playing
![Page 19: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/19.jpg)
Four-way contrasts
Lexical, Free: Nouns, Verbs, Adj, Advcat, town, call, house, hall, smart, fast
Lexical, Bound: including derivational affixesrasp- [raspberry], cran- [cranberry] , -ceive [conceive, receive], un- [unhappy], re-[rewrite]
Functional, Free: Prepositions, Articleswith, at, and, an, the
Functional, Bound: inflectional affixes-s, -ed, -ing, -en [eats, walked, laughing, eaten]
![Page 20: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/20.jpg)
Exercise 1Identify the free and bound morphemes in the following words
walked, talked, danced, arrived playhouse, watchdog, football player drinking, playing, eating import, export, transport raspberry, cranberry invert, convert, divert
Can the following words be decomposed? delight, news, traitor, bed, evening
![Page 21: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/21.jpg)
Exercise 2Identify the lexical and functional morphemes in the following words.Mention if they are free or bound.
politically beautiful between writing raspberries unable nationalization
![Page 22: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/22.jpg)
Inflection vs. Derivation
Derivational suffixes: allow us to make new words Mary is a writer [writeV – writerN] Mary writes for a living [liveV – livingN]
Inflectional suffixes: required in order to make the sentence grammaticalInflected words belong to the same class *Yesterday I walk to class [walkV – walkedV] *I like all my student [studentN – studentsN]
![Page 23: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/23.jpg)
Inflectional Morphology
Examples: [the POS remains the same]
VERBSEAT = eat, eats, ate, eaten, eating
DRINK = drink, drinks, drank, drunk, drinking
PLAY = play, plays, played, played, playing
-s, -ed, -en, -ing are inflectional morphemes
NOUNSPLAY = play, plays
GIRL = girl, girls
SHEEP = sheep, sheep
-s, 0 are inflectional morphemes
![Page 24: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/24.jpg)
Derivational morphology
Two types: Can change the category {N,V,A,Adv}
driveV +er = driverN
eatv + able = eatableadj
girlN + ish = girlishadj
disturb V + ance = disturbance N
Doesn’t have to change the categoryun + doV = undoV
re+fryv = refryv
un+happinessN = unhappinessN
![Page 25: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/25.jpg)
Derivational – more examples
Verbseat – eatable [adj], eatables [noun]drink – drinking [noun] play – player [noun]
-able, -ing, -er are derivational morphemes
Nounsplay – playful [adj], replay [verb]girl – girlish [adj], girlhood [noun]sheep – sheepish[adj]
-ful, re-, -ish, -hood are derivational morphemes
![Page 26: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/26.jpg)
Exercise 3
Each of the words below contains two morphemes – a root and a derivational affix. Decide if the derivational affix changes only the meaning or the class of the root as well.
rewrite hopeless happily
unclear creation happiness
unhappy helpful undo
![Page 27: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/27.jpg)
Null/Zero morpheme
a null morpheme is a morpheme that is realized by a phonologically null affix (an empty string of phonological segments)
a null morpheme is an "invisible" affix It's also called zero morpheme; the process
of adding a null morpheme is called null affixation,
![Page 28: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/28.jpg)
Examples
cat = cat + -0 = ROOT("cat") + SINGULAR cats = cat + -s = ROOT("cat") + PLURAL
sheep = sheep + -0 = ROOT(“sheep") + SINGULAR
sheep = sheep + -0 = ROOT(“sheep") + PLURAL
![Page 29: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/29.jpg)
More examples
darken[verb] = dark [adj] + -en Meaning = make more ‘Adjective’
redden [verb] = red + -en [make more Red]
yellow [verb] = yellow + 0 [make more yellow]
brown [verb] = brown + 0 [make more brown]
blacken [verb] = black + -en [make more black]
![Page 30: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/30.jpg)
Root Morphemes vs Affix morphemes
Root morphemes are morphemes around which larger words are built.
Root morphemes are free or bound.
Affixes are additional morphemes added to roots to create multi- or poly-morphemic words.
Affixes are always bound.
![Page 31: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/31.jpg)
RatsRoot = rat [free morpheme]Affix = -s [bound morpheme]
ProjectRoot = -ject [bound morpheme]Affix = pro- [bound morpheme]
MiceRoot = mouse [free morpheme]Affix = -s [bound morpheme]
AteRoot = eat [free morpheme]Affix = -ed [bound morpheme]
DisgracefulnessRoot = grace [free morpheme]Affixes = dis-, -ful, -ness [bound morpheme]
![Page 32: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/32.jpg)
Affixes
Morphemes added to free forms to make other free forms are called affixes.
Mainly four kinds of affixes:1. Prefixes (at beginning) – “un-” in “unable”
2. Suffixes (at end) – “-ed” in “walked”
3. Circumfixes (at both ends) – “en—en” in enlighten
4. Infixes (in the middle) – “-um-” in kumilad [‘to be red’], fumikas [‘to be strong’]
[ kilad = ‘red’, fikas = ‘strong’ in Bontoc language]
Affixes are bound morphemes.
![Page 33: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/33.jpg)
Prefixes
No prefix can determine the category of a complex word
What does un- mean when it attaches to adjectives?
unkind, unhappy What does un- mean when it attaches to
verbs?
undo, untie
![Page 34: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/34.jpg)
Suffixes
We can represent the fact that the rightmost suffix determines the category of a word for triplets like -
rational, rationalize, rationalization rational = adjective rationalize = verb rationalization = noun
![Page 35: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/35.jpg)
Allomorph
An allomorph is a variant form of a morpheme.
The meaning remains the same, while the sound can vary.
Example: the different forms of past tense morpheme /-ed/ [as we hear] barked, hissed [t] raised, smelled [d] added, trotted [ed]
![Page 36: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/36.jpg)
-s for nouns
Example: the different forms of plural morpheme /-s/ are: [as we read]-s --- cats, dogs, boys, girls-es – watches, churches-0 – sheep
/-s/, /-es/ and 0 are allomorphs of /-s/{If pronunciation is considered, then /-s/, /-z/, /-
iz/ and 0 are allomorphs of /-s/ in the above examples}
![Page 37: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/37.jpg)
Hierarchical Structure within Words the word unlockable is ambiguous
[[un + lock] able]: able to be unlocked [un [lock +able]]: not able-to-be-locked
French History Teacher Old Ladies Hostel Old Bombay Highway
![Page 38: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/38.jpg)
Disgraceful Ungraceful
Adj Adj
/ \ / \
Noun Suffix Prefix Adj
/ \ | | / \
Prefix Noun | | Noun Suffix
| | | | | |
Dis grace ful Un grace ful
![Page 39: Morphology Dr. Radhika Mamidi. Why are we studying morphology? The knowledge of words will help us process language computationally at word level. Knowledge.](https://reader035.fdocuments.in/reader035/viewer/2022081515/56649c925503460f9494d186/html5/thumbnails/39.jpg)
Exercise 4Give the hierarchical structure of the following words
unwanted disfigurement interchangeable maladjusted actors retries unhappiness