Phonology

Phonology - How Speech Sounds Combine
Introduction to Linguistics for Computational Linguists

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Speech Sounds
• Phonetics - Physical basis of speech sounds
– Physiology of pronunciation, perception – Acoustics of speech sounds

• Phonology - Patterns of combination of speech sounds
– Which sequences are allowed (phonotactics) – Effects of context on speech
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Phonology
• Basic elements are phonemes. • Patterns of organization are phonology.
– – – – Structure of phoneme set Syllables, phonotactics (order of phonemes) Processes (adjustments in pronunciation) Rhythm, stress, tempo (not in this course)

• Phonological principles are psychological, sometimes with phonetic (physical) base
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Other Phonology
• Stress, rhythm, intonation
– Stress: ’Verb und Nomen vs. Ver’bundnomen – Rhythm: Nicht! Aufhören! vs. Nicht aufhören! – Intonation: Ich bin der Nächste. vs. Ich bin der Nächste?

• Tempo, intensity (loudness) also • Emphasis (here) on segmental level
– Stress, rhythm, intonation are suprasegmental
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Phoneme Inventory
• Structure in set of phonemes
– cross-classification in phonetic features – multidimensional matrix – place, manner, voice – [p,t,k] vs. [b,d,g] / [f,s,χ] vs. [v,z,-]

• Symmetry, but imperfect
– gaps (German voiced velar fricative) – crowding ([s, ] structurally close) – unique elements [l,R, ]
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Phonotactics
• Phonotactics - allowable phoneme sequences
– reduce combinatorics of sequencing

• Which could be German?
– [frI ] [fstr t ] [kw t ] [kto] [χru t of] [kRil] [ u] [ptero]

• Preserved in “jargon” aphasia • Japanese allows only CV(n), i.e., consonsant followed by vowel perhaps followed by [n]
– Borrowings with final consonants, consonant clusters modified – [besiboru] ‘baseball’ ; [kurIsumasu] ‘Christmas’
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Syllables
• (onset rime) = (onset (nucleus coda)) • Rime determines what rhymes (in one syll.)
– groß, los [os]; Rad, Tat [at]; Zahl, Kanal [al]

• Nucleus always vowel • Possible clusters largely determined by sonority

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Sonority and Syllables
• Observation: mirror antisymmetry in consonant order in clusters in onset vs. coda
– [pl ts], [ lp]; [tr p], [fart]; [flai ], [h lft]

• Sonority - relative prominence
100 80 60 40 20 0 Vowels Liquids (l,R) Nasals Stops, etc. Sonority

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Sonority in Syllable
• Sonority climbs toward peak, then declines

Prinz

p

r

I

n

ts

qualmt

k

w

a

l

m

t

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Phonological Processes
• Compare Susi und Peter/Tom/Gabi spoken quickly • [zu.zi.m.pet R] / [n.t m] / [ gabi] • ‘und’ is pronounced [m/n/ ] • Similary /n/ in Es könnte dann passen/gehen • Sloppy?
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Nasal Assimilation
• Speech requires lots of coordination • Nerves, muscles are preparing several segments ahead • Often we see effects in adjacent phonemes place n C

n adjusts its place of articulation to anticipate the following consonant

• Processes modify phonemes

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Aspiration Revisited
• Recall from Phonetics lecture that voiceless stops are normally aspirated, i.e. voicing starts well after stop is released release • Unaspirated [b,d,g] stop voicing • Aspirated [p,t,k] -- note puff! stop voicing 12

Aspiration
• [p,t,k] unaspirated after [ ,s]
– [ p k] Speck, [ tIm ] Stimme, [ski] Ski

• We note aspiration with [ph], etc.
– Tücke/Stücke [th k ]/ [ t k ]

• [th], [t] are allophones (variants) of the same phoneme; likewise [ph], [p] • Since they are found in different contexts, they are in complementary distribution
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Informal Rule Notation
• C[-voi,+stop] → Ch / . __ V • “Voiceless Stops become aspirated in the environment (/) after syllable begin (.) and before vowels”
– Tücke /t k / → [th .kh ] – phonemes → “are realized as” phones
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Final Devoicing
• Auslautverhärtung
– lobe [lob. ] but lob! [lop] – blase [blaz. ] but blas! [blas] – steige [ taig. ] but steig! [ taik]

• C → C[-voice] / __ #,

– where ‘#’ is a word boundary – or morpheme boundary? --See lecture on Morphology. – or syllable boundary? Wagner [w g.n R] / [w k.n R]
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Release
• /p,t,k/ may be unreleased finally • Morgen geht Peter weg. [geth] or [get-] • Alternative pronunciations arising through optional processes also allophones, said to be in free variation
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Releasing
• Stops before other stops are normally not released
– [ kt], [kIpt] Akt, kipt – IPA [ k-t], [kIp-t]

• Third allophone of /p/: [ph,p-,p]
– in complementary distribution and/or free variation

• C[+stop] → C- / __ C [+stop]
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Finding Phonemes
• To determine phonemic inventory, linguists analyze all (apparent) cases of complementary distribution and free variation • Earlier seen as part of automatic (discovery) procedure, which is infeasible.
– But still standard procedure
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Nasalisation
• Vowels before nasals ([n,m, ]) are pronounced with velum lowered
– eng [ ] vs. Eck(e) [ k] – tilde normally above the nasalized symbol

• V → V~ / __ N, where N is [n,m] or [ ]
– allophone in complentary distribution

• French uses nasalized vowels contrastively
– beau [bo] vs bon [bo]
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Intrusive [t], etc.
• Why does Benz [b nts] rhyme with Jens [j ns]? • ∅ → t / n __ s • Sims [zIms] or [zImps]? Example with [ ]?
– Hamster [h mp.st R], des Lamms [l mps]

• See Tim und Struppi detectives Schultze und Schulze, English Thomson and Thompson
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Whispered Sonorants
• [l,R,w,j] are sonorants (likewise nasals) • Pronounced after voiceless stops, they are also voiceless (because of aspiration)
– Prinz [pRInts], Tratsch [tRat ], Quatsch [kw t ], Klauen [klau n]

• S → S / Ch __
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Weak Syllables
• Second, unstressed syllables followed by sonorants
– Boden [bo.d n] or [bod.n] – Sattel [z t. l] or [z t.l] – Butter [b t. R], [b t R], or [b t ]

• •

R→

R/

__ #, where ‘#’ signifies end of word
R

– kleinere [klain R ], not [klain

],
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S → S/ __ #

Nasals in Weak Syllables
• Lappen [l p.m], loben [lob.m], kommen [kom.m] • Boden [bod.n], Ratten [R t.n], lassen [l s.n] • packen [p k. ], sagen [z g. ], singen [zI . ] • Same reduction to syllabic sonorant plus assimilation in place. • Can create unusual pronunciations!
– kommen [kom:], rennen [r n:], singen [zI :]
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Reduced Nasals after Labiodentals
• Laufen [lauf.n], [lauf.m], [lauf. ]; • Löwen [l v.n], [l v.m], [l v. ]; • [ ] is a labiodental nasal (i.e., shares place of articulation with [f,v]) • [ ] is a syllabic version
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Velar/Palatal Fricative
• [ ] (velar fricative) also pronounced palatally
– Aachen, [a . n], Bach [b ], Buch [bu ], Loch [l ] . R] – ich [i ], echt [ t], Bücher [b . R], Löcher [l

•

→

/ V[+front] __

– complementary distribution, allophones

• But liebchen [lib. n], Mädchen [met. n] -Why palatal? • → / V[+back] __ ?? (with as basic)
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Phonemic Analysis
• liebchen [lib. n] palatal, not after front V • → / V[+back] __ but Kuhchen/Kuchen • Frauchen [fRau. n] vs. Rauchen [Rau . n]
– Near-minimal pair: with → rule, no account
• we don’t wish to say that -chen is [- n] since phonological processes work on phonemes, and (under → rule), is the phoneme

–

→

preferable n] has no because of the syllable (‘.’)
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• [fRau.

Why are there Phonological Processes?
• Speech is hard -- 2 wd./sec. (~ 10 phon/sec) • Signals reach muscles at different speeds, which then contract in varying times
– long nerve pathway to intercostals (in chest) – velum is slow compared to tongue

• Some processes simply make speech easier
– nasal assimilation, velar/palatal alternation [ / ], nasalization of vowels
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Why Phonological Processes?
• Speech is also hard to understand • Some processes make sounds more distinct
– aspiration – exaggerated release of final stops
• Halt! [h lth] Gut! [guth] (compare [gut-])

– vowel lengthening under emphasis
• Das tue ich nie [d s tu i ni:]

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How “Real” is Phonology?
• Could patterns be accidental? • Speakers apply native phonology even when dealing with unknown material
– inventory – phonotactics – processes

• Evidence in generality, application to foreign material (accents/mishearings), even errors
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Inventory
• We tend to hear/pronounce foreign languages as composed of “our” sounds
– Eng. / then/thin pronounced [z/d;s/t] by French, Germans – German front rounded vowels hard for English, Russian, Spanish speakers [y, , , ] – Spanish trilled [r], English retroflex [r] hard for French, German speakers Sp. perro, Eng. Red – Initial [h] hard for French speakers • Eng. home [om]; Germ. Haus [aus] – Japanese r/l “Conglaturations on Erection!”
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Phonotactics
• We find it hard to pronounce sounds out of place -- even if they exist in our language
– Dutch [s …] used to detect Germans: Scheveningen – Sp. has sequences [prjeto] (prieto), [kljente] (cliente), [krwel] (cruel) -- Eng./Ger. tend to mispronounce [prijeto], [klijente], [kruwel] – Vietnamese initial [ ] hard for Europeans • Ngu Van Thieu [ u ...] “simplified” to [nju ...]

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Processes
• We mishear/mispronounce by using native language processes in foreign languages
– French hear English/German as “nasal” and vice versa
• nasality in unexpected places Fr. [bo] Eng. [bon]

– English/German aspiration interferes w. French
• French [p] , Eng./German [b] similar VOT’s ; • French accent in English ‘You pig!’ [ju big]

– German final devoicing in English
• ‘Child’ [t ailt], ‘could’ [k t]
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Psychological Reality
• Processes apply where they were never heard
– foreign speech – errors ‘tip of the slung’ [thIp …] – nonsense words
• “’Twas brillig and the slithy toves” … [thovz]

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Bigger Picture
• Processes here tip of iceberg
– [k] in Kind [kInd] further front than in Kuh [ku]

• Constant anticipation, perserverance
– Effect of consonant on formants [ku] vs. [tu]

• Creates redundancy in signal
– enable understanding even when perception lags

• Shifts information to acoustically prominent elements (vowels)

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Phonology
• Patterns of combination of speech sounds
– Inventory of basic sounds – Which sequences are allowed (phonotactics) – Processes -- effects of context on speech

• Emphasis (here) on segmental level
– Stress, rhythm, & intonation are suprasegmental

• Phonology involves imposition of structure
– seen in novel applications (foreign words, nonsense words, and even errors)
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Phonology
• Phonological processes serve to ease production and perception of speech • Even apparent production-simplifying processes may enhance redundancy, ensuring perception.

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