Tone contour

Tone contour is the how the pitch varies over a syllable for a tone in a tonal language. It is usually denoted by a string of two or three numbers, or an equivalent pictogram.

Chao's Tone Letters
For Chinese, which is a tonal language, the pronunciation of a syllable in a particular tone gives adds information that a listener fluent in that language can discern. For Mandarin Chinese, there are four basic tones.

A method for indicating the tone contour, usually attributed to Yuen Ren Chao, may be visualised as a stave of music of five horizontal lines, each representing a different pitch level. The pitch levels are numbered from 1 to 5, the lowest being 1 and the highest being 5.

The Standard Mandarin third tone has a tone contour /214/, showing a pitch that dips and then rises.

Examples of level tone contours are /11/, /22/, /33/, /44/ and /55/.

Falling tone contours include /51/, /31/, /53/, etc.

Rising tone contours include /13/, /35/, /15/, etc.

Some people write short tones with only one digit to emphasis the shortness. For example, a high-pitched short utterance would have a tone contour of /5/, whereas a long, level high tone would be /55/. These "abrupt tones" typically have either an unvoiced consonant or a glottal stop at the end which abruptly cuts off the vowel sound. However, other people prefer keeping the digit doubled to avoid confusion with the tone numbers.

Other usage
In the study of African and Meso-American languages, linguists also use numbers to denote pitches. However, in these cases, 1 usually denotes the highest pitch, while 5 denotes the lowest pitch. Readers should pay attention to the context of different linguistic traditions.

Tonsprache Contour de ton 聲調輪廓