LECTURE ONE P H O N E T I C S

Transcription

1 LECTURE ONE P H O N E T I C S 1. Phones Speech is commonly thought of a sequence of phones, more or less unitary segments of the stream of speech. The standard form of phonetic transcription is the International Phonetic Alphabet, a large symbol set promulgated by a scholarly society called the International Phonetic Association (both the alphabet and the association may be abbreviated IPA ; the IPA website: ) 1

2 2

3 2. Speech physiology The three major regions of the vocal tract are the nasal cavity, the oral cavity (less pretentiously, the mouth), and the pharynx, which is located behind the tongue but above the larynx. The most crucial organ of speech is the tongue. Bear in mind that just looking in a mirror gives you a poor idea of the shape of the human tongue, because you can only see the tongue s forward extension. In reality, the tongue is more of a lump; when at rest it is fairly round in shape except for highly visible flange up front. The round main section is extremely mobile and flexible, and can move in all directions. The parts of the tongue that we will refer to are the tip (or apex), the blade (= the forward flange), and the body (the main rounded part). The lips and teeth need no comment other than that they are both important for speech. The next important landmark, going backward, is the alveolar ridge. Most people can feel this ridge by placing the tongue a little further back in the mouth than the upper inside edge of the front teeth. The alveolar ridge forms a useful boundary line on the upper surface of the mouth. The expanse behind the alveolar ridge is called the palate. The palate is divided into a hard, bony section in front called the hard palate and a soft fleshy section in back called the soft palate or velum (Latin for sail ). The velum is mobile. If you know how to produce nasalized vowels (as in French), you can see it moving by looking in a mirror, placing your tongue as low as possible, and alternating between saying nasalized and normal vowels. The main function of the velum in speech is to control nasality. Most often, the velum is raised up to block of the nasal passage. When it is lowered, air may pass out the nose and we get a nasal sound. 3

4 The little hanging object at the tip of the velum, made famous by screaming cartoon characters, is called the uvula. It is used in sound production in many languages (for example, French, Persian, and Arabic), but not in English. The pharynx is the space behind the tongue, invisible to us unless we use a mirror. This space can be made smaller by retracting the tongue body down into it. At the bottom of the pharynx is the larynx, or voice box. This is a highly complex structure of cartilage, muscle, and ligaments. The crucial elements of the larynx are the vocal cords. These are not really cords, but flaps that come in from both sides. The vocal cords can close off the flow of air to varying degrees. The gap between the vocal cords is called the glottis. 2.1 Voiced and voiceless phones 2.2 Oral and nasal phones Sounds pronounced through the nose are nasal (m, n, and ng); those pronounced through the mouth are oral (all other consonants. 2.3 Place of articulation By combining information about place of articulation with information about manner, we can arrive at complete descriptions of English consonants. 4

5 (a) Bilabial sounds are made by touching the upper and lower lips together. English has a voiceless bilabial stop [p], a voiced bilabial stop [b], and a (voiced) bilabial nasal [m]. Note the standard form for describing a consonant: the format is VOICING-PLACE- MANNER. In the case of nasals and approximants, which are almost always voiced, it is permissible to specify only place and manner. (b) Labio-dental sounds are made by touching the lower lip to the upper teeth. English has a voiceless labio-dental fricative, [f], and a voiced one, [v]. Labio-dental stops and nasals are very rare, though English speakers make them if they try to say [p], [b], or [m] while smiling. (c) Dental sounds are made by touching the tongue to the upper teeth. This can be done in a number of ways. If the tongue is stuck out beyond the teeth, the sound is called an interdental, though we will not worry about such fine distinctions. English has a voiceless interdental fricative [θ] (as in thin), and a voiced one [ð] (as in then). (d) Alveolar sounds are made by touching the tip or blade of the tongue to a location just forward of the alveolar ridge. English has several alveolar consonants. There is a voiceless alveolar stop [t], a voiced alveolar stop [d], voiceless and voiced alveolar fricatives [s] and [z], an alveolar nasal [n], and an alveolar lateral liquid [l]. All these phonetic symbols correspond to English spelling. (e) Palato-alveolar sounds are made by touching the blade of the tongue to a location just behind the alveolar ridge. English has a voiceless palato-alveolar fricative [ʃ] (as in shoe), a voiced palato-alveolar fricative [ ] (as in vision), a voiceless palato-alveolar affricate [tʃ], (as in church), and voiced palato-alveolar affricate [dʒ] (as in judge). (f) Palatal sounds are made by moving the body of the tongue forward toward the hard palate. English has just one palatal sound, the palatal glide [j], as in year. (f) Velar sounds are made by touching the body of the tongue to the velum. English has three velar sounds: a voiceless velar stop [k] (as in cat or king), a voiced velar stop [g] (as in goat), and a velar nasal [ŋ] (as in sing). Note that in this case English uses a sequence of two letters to spell what is phonetically a single sound. (g) Glottal sounds are made by moving the vocal cords close to one another. English has a voiceless glottal fricative [h]. 3. Types of phones 3.1. Consonants 5

6 6

7 3.2. Vowels Vowels differ from consonants in that they do not have real places of articulation, that is to say, points of severe constriction in the vocal tract. Rather, the vocal tract as a whole acts as a resonating chamber. By modifying the shape of this chamber using movements of the tongue, jaw, and lips, one imparts different sound qualities to the basic noise made by the vocal cords. An analogy can be made with brass instruments. The vocal cords by themselves make a rather ugly buzz, just like the mouthpiece of a trumpet does when played by itself. The buzz is given its more pleasant characteristic quality by being passed through a resonating chamber (for example, a trumpet or a vocal tract). The quality of the sound is 7

8 determined by the shape of the chamber; thus vowels of English are similar to notes played by the same trumpet with different mutes placed inside. There are three basic modifications that one can make to the shape of the vocal tract. Vowels are described by specifying the amount of each modification used. Rounding One obvious modification one can make to the shape of the vocal tract is to round the lips, thus narrowing the passage at the exit. This happens, for example, in the vowels of boot [u], book [ʊ], and boat [oʊ]. These are called rounded or simply round vowels. Other vowels, such as the [i] of beet or the [a] of cot, are called unrounded. (Warning: you may speak a dialect of English that has little lip rounding. The really rounded vowels are found more easily in other languages.) Height Another modification one can make to the shape of the vocal tract is to make passage through the mouth wider or narrower. Widening is accomplished by opening the jaw and/or lowering the body of the tongue towards the bottom of the mouth. Narrowing is accomplished by raising the jaw and raising the body of the tongue. The terminology for describing these changes is based on the height of the tongue body (without regard to whether this is due to jaw movement or tongue movement). Vowels are classified as high, mid, or low, depending on tongue body position. In effect, high vowels have a narrow passage for the air to pass through, and low vowels have a wide passage. Examples of high vowels in English are [i], the vowel of beat, and [u], the vowel of boot. Example of low vowels are [ɑ], the vowel of cot, and [æ], the vowel of bat. You can feel the oral passage widening and narrowing if you pronounce a sequence of vowels that alternates between high and low, such as [i æ i æ i æ i æ]. Backness The third primary way of changing the vocal tract shape is to place the body of the tongue towards the front part of the mouth or towards the back. Vowels so made are called front and back vowels. For example, [i] (beat) is a high front vowel, and [u] (boot) is a high back vowel (which is also rounded). You can feel the tongue moving forwards and backwards if you pronounce the sequence [i u i u i u i u]. 8

9 The features allow us to describe a segment phonetically in a compact notation, called a feature matrix. For example, the vowel [i] is expressed in features as follows: 3.3. Obstruents and sonorants 9

10 4. Suprasegmentals It is often difficult or impossible to identify the quality of a suprasegmental feature without comparing different segments and different utterances Length: Some speech sounds are longer than others by comparison, and long vowels and consonants are indicated by a pair of arrows following the long segments -these speech sounds are long only by comparison to their regular "short" pronunciation Intonation: The pattern of pitch movements across a stretch of speech, to change its meaning -a rising intonation at the end of an utterance makes it sound like a question, while a falling intonation makes it sound like a statement Pitch accents: A change in fundamental frequency in the middle of an utterance -words with a higher/lower pitch than the surrounding words are perceived as very prominent and can change the same string of words to fit different situations Edge tones: A change in fundamental frequency at the end of a phrase, before a perceived break -a falling pitch is usually a for a statement (sentence-final intonation), a rising pitch indicates a question (question intonation), and a fall with a slight rise indicates that the speaker is not yet done speaking (continuation rise) Tone: The pitch at which syllables are pronounced can sometimes change a word's meaning in a tone language such as Mandarin -there are two types, level (steady tone throughout a syllable) and contour (a single syllable with a tone gliding from one level to another -a rising tone or a falling tone) Tones in a tone language are at least somewhat relative, so a given syllable would be high in comparison to other syllables spoken by the same speaker -knowledge of the speaker's physical characteristics (gender, height, size) can help to predict this Stress: A stressed syllable is more prominent (longer, louder, and usually contain full vowels) than an unstressed one -primary stress is indicated with ['] after a syllable, secondary stress is marked with [,] after a symbol, and tertiary stress is not marked Full vowels are produced with more extreme positions of the tongue, while reduced vowels are pronounced closer to the mid-central position In some languages, stress placement is predictable, but in languages such as Russian and English, stress must be learned for each individual word and can often cause a difference in meaning (bla'ckboard vs black bo'ard -a historical feature in schools vs a simple black piece of wood) These suprasegmental features have no meaning or function in isolation, and can only be discovered by comparison of different syllables -while the [a] symbol always has a specific meaning, the ['] symbol does not 10