Tonal Languages

Tonal Languages (or tone languages), languages where the meaning of some words is distinguished by raising and lowering the pitch with the voice, in contrast to stress languages. The lexically distinct pitches are called tones. In Cantonese Chinese, for example, the syllable yau has six meanings depending on its tone: “worry”, “thin”, “paint”, “oil”, “again”, and “have”. This is distinct from intonation, in which pitch changes may signal sentence-level meanings such as questions or surprise. All languages seem to use pitch for these sentence-level meanings, but some 60 to 70 per cent are like Cantonese in also using it for word meanings. This includes most of the languages of sub-Saharan Africa, East and South East Asia, and Central America; many in North America, South America, and the Pacific; and even a number of languages of Western Europe, such as Swedish and some varieties of Dutch. The only continent that seems to have no tonal languages is Australia.

It is possible to contrast up to four different level tones, as in the West African language Grebo, and probably five, as in the Mexican language Trique. The most widespread systems are two-tone languages, such as Haya (Tanzania) or Dagaare (Ghana), and three-tone languages such as Yoruba (Nigeria). Phonetically, a language may have far more differences as a result of processes like downstep, a common process that lowers high (H) tones to mid (M) after a low (L) tone, so that an H-L-H sequence is phonetically more like H-L-M. In addition to different levels, languages may also distinguish between level tones and contour tones: rising tones, falling tones, or even more complex rise-falls or fall-rises. Two contours of the same shape seem to be the maximum, although there are rare reports of three, for example Chatino (Mexico).

Pitch is controlled by the larynx in ways that are not fully understood, but that include varying the tension of the vocal chords, and adjusting the height of the larynx. Because these laryngeal mechanisms also play a role in voicing (such as the vibration of vocal chords found in b but not in p), in many languages a historical contrast between voiced and voiceless syllable-initial consonants gave rise to a contrast between lower and higher tones on the following vowel. This process is known as tonogenesis, and is well documented and understood, particularly in the languages of East and South East Asia.

Linguists working on tone have made two striking claims. First, tones have a high degree of independence from the vowels on which they are pronounced, very much like the melody of a song is separate from the lyrics. As a result they sometimes move around within the word, and they may survive when their vowel deletes. Second, contour tones are not indivisible units but instead are composed of sequences of level tones pronounced in sequence on a single syllable.

For example, in the Bantu language Zigula (Tanzania) every form of the verb lombez is pronounced with one high-toned syllable, shown by an acute accent. However, the tone does not stay on one vowel, but moves rightwards onto the penultimate syllable of the suffixed verb: ku-lombéz-a “to request”, ku-lombez-éz-a “to request for”, and ku-lombez-ez-án-a “to request for each other”.

Sometimes one tone spreads out over several syllables, and conversely sometimes two or more tones are pronounced on a single syllable. In a Papua New Guinea language, Siane, a monosyllabic LH noun shows up with the L tone on the noun root, and the H tone on any suffix yoL-teH “fire-my”. Only if there is no suffix do the two tones surface on the noun itself, forming a rising contour: yoLH “fire”. Some tones may not originate from a vowel at all. These floating tones manifest their presence only when they attach to a neighbouring vowel. In Cantonese there is a suffix that denotes familiarity. It consists solely of an H tone, and changes the low-toned yipL to rising LH.

Lexical tone is also used for grammatical purposes. In many Bantu languages it signals tense and aspect distinctions, so that in the North Karanga dialect of Shona bik-is-a means “make cook” but bik-ís-a, with an H tone on the second syllable, means “didn’t make cook”.

Accentual languages, like Japanese or Lithuanian, are usually considered to be a type of tonal language. In these languages, tone is linked to a particular syllable, and does not move around.