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Phonology I. Phonemes and Simple Rules. Connecting with last week. Remember last week: the physics of speech. And, the idea that the consonant and vowel sounds we make have properties that can be described in terms of places, manners, etc.
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Phonology I Phonemes and Simple Rules
Connecting with last week • Remember last week: the physics of speech. And, the idea that the consonant and vowel sounds we make have properties that can be described in terms of places, manners, etc. • A striking fact: There’s a sense in which all of us are producing physically different sounds (and hearing, then, an infinite number of different“speech events”). Yet no matter who says “cat”, I recognize this as the word cat in English. How can that be? • Answer: Speech sounds are categorized by in terms of features; these features are the basic objects of phonology.
Example • Take, from the last slide, my example of cat, I.e., /kæt/. • Taking just the first segment here, the consonant that we write as k in the IPA • This is what we call a voiceless velar obstruent • In the phonology, we posit that /k/ is a complex of features; though different features are sometimes found, something like this: k = [+cons, +back, +obst, -voc] (cons = consonant; back is a place feature; obst = obstruent, voc = voice) • Notice, then, that /k/ differs from /g/ in terms of the voc feature: /k/ is [-voc], /g/ is [+voc] • A large part of the sounds system of language operates in terms of these features
Features • Remember that when we look at the physics of speech, we can make very fine-grained distinctions • Categorizing speech sounds in terms of features is a way of eliminating that detail, in a way. • So, for example, as far as phonology there is not an infinite set of degrees between voicelessness and being voiced • A sound either counts as voiced, or not; I.e., [±voc]
Example, cont. • Let’s take an example from English nouns. We write plurals with -s most of the time. Notice, though, that the plural morpheme has different pronunciations on different nouns: • Dogs • Cats • Zebras • Churches • Lemons • Etc.. • If you listen carefully, you’ll find that it’s sometimes /s/, sometimes /z/, and sometimes /@z/ (that’s a schwa) • Why is that?
The plural example • Think of different ways the change in the plural morpheme’s sound form can be accounted for • In the worst case scenario, speakers would just have to memorize which sound to use with which noun. Sometimes there’s a lot of memorization like this in language, but this isn’t one of those cases • Instead, the form of the plural is correlated with the final sound of the noun: • /-s/: cat, clock, heap, oaf • /-z/: reed, log, flub, drive • /-@z/: (think about this one….) • Try it with new nouns; Bach, glog • Focus on the /s/ versus /z/ plurals. We don’t want to just list the consonants they come after; e.g. we don’t want to say “plural is pronounced /s/ after /t/, /k/, /p/, /f/”
Why not? • We don’t want to say that because a list of consonants like that is in some sense arbitrary: it’s just a list. Phonology doesn’t work in terms of arbitrary lists! • But something systematic connects all the consonants on the /s/ list, and all those on the /z/ list; it’s the feature [±voc]. • So what we want to say is this: • The /-s/ form of plural is found after C[-voc] • The /-z/ form of plural is found after C[+voc] • In other words: The generalization about this part of English is stated in a way that makes reference to distinctive features. • Probably here we want to say that plural is “basically” /-z/, and that it gets devoiced next to voiceless consonants. We’ll talk about rules like this later.
Phonemes • Features are combined into larger units to make up what we think of as speech sounds. Among those sounds, some are special. • The individual, distinctive sounds of a language are called phonemes • We saw the different consonants and vowels that are part of English in the last lecture • As we discussed before, this inventory will differ to some extent by the variety of English under consideration • What we’re more concerned with here is this-- why is it that we say we have e.g. both [t] and [th] sounds in English, but only one phoneme /t/?
The basic insight • We saw that in some contexts, the sound we write with t is realized as [t], and in others, as [th] (remember this works for other voiceless stops as well): • till vs. still, [t] vs. [th] • As far as the sound system of English goes, though, the difference between unaspirated and aspirated t’s doesn’t do any real work in distinguishing words or morphemes from each other • Another way of putting this is that the difference between[t] vs. [th] is not distinctive.
Being Distinctive • We refer to the phonemes like /t/, /d/, etc. that are part of English phonology as distinctive because they make contrasts between different words • This can be illustrated for stops by using minimal pairs: a pair of words that differ in only one phoneme: pill bill [p] vs. [b] till dill [t] vs. [d] kill gill [k] vs. [g] These pairs show that voicing is distinctive for these stops • The kind of analysis can be applied to vowels as well. • We write the phonemes in /…./ as an indication that these are distinctive in the phonology of the language
Differences that are not distinctive • We started, though, by noting that some aspects of pronunciation are not distinctive. • Remember: aspiration (using /p/ now) pit vs. spit • The former [p] is aspirated, but the [p] in the latter is not • But: the distinction between aspirated and non-aspirated [p] is not distinctive in English (although it is in other languages). That is, in English there are no pairs like [pIt] ‘hole in the ground, etc.’ [phIt] (whatever this might be) • We see from this example that aspiration is not distinctive in English (technically we would have to do more test that go beyond /p/, but you get the point)
Phonemes and Allophones • Sometimes the same phoneme is pronounced in different ways depending on its context • The variants of a phoneme are called allophones of that phoneme • When we are talking about such distinctions, the phoneme is in slashes /…/ and the allophones are in square brackets […] • The aspiration of e.g. /p/ is a case of this type; we say that /p/ in English has the allophones [p] and [ph]
Transcribing differences • When we transcribe speech sounds using our IPA notation, we may do so in different ways. • If we are interested in every phonetic detail, we would indicate effects like aspiration in English, even if it is not distinctive • If we are interested more in the phonological inventory, we would omit the aspiration, as it is not distinctive • For our purposes we will be concentrating mostly on the latter type • When we focus on phonology, an abstract representation, we use slashes, e.g. /p/
Phonemes and Allophones, cont. • So, to continue with our example, the phoneme /p/ appears in each of the following words: pit spit • Remember that we are interested in generalizations about sound structure. In particular, the rule for aspiration in English is like this: • English voiceless stops are • Aspirated if word initial, or syllable-initial preceding a stressed vowel: Compare récord vs. recórd b. Otherwise unaspirated.
Phonemes and their distributions • Above we saw some simple minimal pairs of words that illustrate how we determine what the phonemes of a language are • Other cases of distinctive features lead to some interesting observations • Consider the nasals: • rum run rung • These phonemes can all appear at the end of the word; but, [ng], unlike the other two, has the property that it never occurs word-initially in English • map nap *ngap • Although it occurs only at the end of the word, it’s still a phoneme, as seen in run vs rung, or sin vs. sing, etc.
Applying some thinking • One way of seeing whether or not we are dealing with two different phonemes or two allophones of the same phoneme involves what is called complementary distribution. • We have already seen some things about distribution before • For example, /ng/ does not occur in word-internal position • Think now about our minimal pairs like pill and bill. In these words, the p and b sounds occur in the same distributional position (word-initially) • Another way of putting this is that the p sound and the b sound have a shared distribution; that is, they are not in complementary distribution, where one is found where the other is not
Distribution… • Consider /f/ and /v/ in this light. In Modern English it is easy to find minimal pairs: • fat vs. vat • safer vs. saver • I.e., these sounds are not in complementary distribution. They are two phonemes. • In Old English, though, this was not the case: • hlaford [v] ‘lord’ • æfter [f] ‘after’ • heofon [v] ‘heaven’ • fisc [f] ‘fish’ • ofer [v] ‘over’ • healf [f] ‘half’
Cross-Linguistic Differences • Some sound differences are systematic in a lanuage, but are not phonemic. In another language, though, that sound difference might be phonemic…. • Everyone has encountered a language that contains a speech sound that is not in their native language • As a general point, languages differ greatly both in terms of how many phonemes they have and in terms of which phonemes they have • Number of phonemes: • Many: Some Khoisan languages, around 140 phonemes • Few: E.g. Hawaiian, 13 phonemes
Other languages • Like it says above, languages have different numbers of phonemes • In some cases, a contrast that is not phonemic in one language is phonemic in another • E.g. Hindi has contrastive voiced/voiceless like English, but aspiration is also contrastive: bal ‘hair’ dal ‘lentil’ gal ‘cheek’ pal ‘take care of’ tal ‘beat’ kal ‘era’ phal ‘knife blade’ thal ‘plate’ khal ‘skin’ Listen to these (and more…) at: http://www.phonetics.ucla.edu/vowels/chapter12/hindi.html