Basics of Tone
There are basically two kinds of tone systems - pitch accents, and proper tonal languages. As in a stress accent system, in a pitch accent system one syllable per word is the stressed syllable. The difference is the accent is realised as a change in pitch, not stress. For example, Japanese syllables can have either high or low tone. In most words, the first syllable is low, and all the following syllables are high, until the stressed syllable - after the stressed syllable the pitch falls again. If you know which syllable is stressed, then you know the whole pitch pattern of the word. Each word has one and only one fall in pitch [some are unstressed and so remain high pitch, and if the stress is on the first syllable, then the first syllable is obviously high].
In tonal languages, each syllable has a tone - the tone is as much an important part of the syllable as the vowel [in Chinese, the tone carries just as much information as the vowel - saying a toneless syllable is just as hard to understand as saying the syllable with the correct tone but no vowel]. There are basically two types of tone that a syllable can have - a level tone, where the whole syllable is at the same pitch [Low, High, Medium,...] and contour tones, where the pitch changes [Rising, Falling, Falling-Rising].
For ease, H M L F R will be used instead of high, mid, low, falling, rising. If there are different falling or rising tones, they can be distinguished by HM [falling from heigh to mid ], LH etc.
Tone Systems in Languages
Different languages vary a lot in how many different tones they have
From A Model of Tone Systems. Jean-Marie Hombert. [Department of Linguistics. University of California, Los Angeles]
About 30% of the world’s languages are tonal - “This figure would go up to about 50% if we would consider a sample of languages in which each language family would be represented by a umber of languages proportional to the actual number it contains. This discrepancy between the two figures comes from the fact that most of the languages spoken in areas of great linguistic diversity [e.g. Chinese and southeast Asian languages, Papuan New Guinea languages and Northwestern Bantu languages] are tonal.”
30% of tonal languages have 2 tones
30% have 3 tones
15% have 4 tones
10% have 5 tones
10% have 6 or more
Of 2 tone systems:
~90% are H, L
3 tone :
~ 65% are H, M , L
~ 20% are H, L, F
4 tones:
~ 40% are H, L, F, R
~ 30% are H, M, L, F
5 tones:
~ 60% are H, M, L, F, R
6 tones:
~ 60% are 2 level tones [usually L, M], 2 Falling tones [HM, ML] 2 rising tones [LM, MH
7, 8 tones:
~no clear patterns found
[end of material taken from that link]
Tonal Universals [“They’re more .. guidelines than what you’d call actual rules”]
There are also a few universals of tone systems.
One is that no language distinguishes more than 5 tone levels.
This means that there are a maximum of 5 level tones possible in any language, and all contour tones must start and stop on one of those 5 levels. These are often numbered 1 being the lowest, 5 the highest. Tones can thus be written as 55 - a high level tone [the first tone in Mandarin Chinese], 35 a rising tone from the mid-level to the high level [The rising tone in Mandarin] etc.
Some more universals, taken from SIL Electronic Working Papers, SILEWP 2007-007:
a. A larger number of tone levels occupy a larger pitch range than a smaller number
(~20 Hz for two tones, 50 Hz for four tones)
b. Systems in which high tones are marked are more frequent than systems in which
low tones are marked.
c. If a language has contour tones, it also has level tones.
d. A language with complex contours also has simple contours.
e. Rules raising tones are more common than rules lowering them.
f. Perseverative rules are more common than anticipatory ones.
g. Tonal polarity is more common than polarity with other features.
h. Lower vowels tend to have lower tone.
i. Low-toned vowels tend to be longer than high-toned ones.
j. Vowels with rising tone tend to be longer than vowels with falling tone.
With the exception of the (a), these universals are general tendencies rather than true universals. (a) means that if A system has two tones, then the difference in pitch between the highest and lowest will be different than the difference in pitch between the highest and lowest tone of a five tone system. So the H and L in different languages won’t always sound the same.
How do tones behave? Interactions
This is the interesting bit.
If you’re planning a tonal conlang, you need a way to represent the interactions of tones in order to plan phonotactics. There are lots of these, I would imagine, but the only one I know, and which appears to be rather good, is autosegmental theory.
Autosegmental theory treats the tones as being a separate feature that is attahced to the syllables, but that can move around independantly. Little diagrams like this are very useful:
Code: Select all
H H H L H
| | | | |
ma ma ror ire
This is the Kikuyu word “they looked at them.”
The structure of the Kikuyu word is quite simple
Code: Select all
Subject (Object) Root Tense
to ‘we’ mo ‘him’ ror ‘look at’
ma ‘they’ ma ‘them’ tom ‘send’ ire
Code: Select all
to ma mo ma ror tom ire
L H L H L H H
* The subject “to” [we] always has L tone
* The subject “ma” [they] always has H tone
* The morpheme immediately after the subject [ie object or root] always has the same tone as the subject - regardless of what its own tone.
* The last syllable of the tense suffix “ire” is always high, but the first syllable varies: if the root is “ror” [look at], the first syllable of “ire” is L, if the root is “tom” [send] then the first syllable is H.
Why such apparently random restrictions?
This can be anaysed quite neatly using the little tie line diagrams mentioned above.
Consider the word “ma mo tom ire” “they sent him.” Its tones are:
Code: Select all
H L H H
| | | |
ma mo tom ire
The tones really all want to be at the right edge - on the final syllable. This is impossible in Kikuyu - this would create a HLH contour on the final syllable, which is against the languages phonotactics: level tones only. In Kikuyu, there is a condition [the well-formedness condition]: each tone can be attached to only one vowel, and vice versa [this isn’t true in all languages]. Two high tones can merge togetehr though.
So the maximum possible right drift of tones is
Code: Select all
H L H H
\ \ \ |
ma mo tom ire
The tone pattern of the word has changed from
HLHH to
0HLH
This has left the first syllable [the subject] toneless. But remember Kikuyu’s well formedness condition: each vowel must be attached to one and only one tone; and each tone must be attached to one and only one vowel. This requires that
1. No tone can be linked to more than one vowel
2. No vowel can be toneless.
One of these must be violated - in Kikuyu, the second takes priority, and so the word becomes
Code: Select all
H L H H
| \ \ \ |
ma mo tom ire
Thus the word has changed from
HLHH to
HHLH.
All the other observations of the tone distribution above can be explained in the same way: by the tones trying to drift to the right as far as they can.
More complicated systems - contours
This same analysis can be used for contour tones too. Contour tones are analysed as sequences of H and L tones on one vowel:
Code: Select all
H L F R
H L HL LH
| | \| |/
ma ma ma ma
imi+ari = imyari
ku+ari = kwari
* If the noun ends in a consonant, there is no tone change - unlike Kikuyu, no tones drift.
* If the noun ends in a high vowel with H tone, there is also no tone change
* if the noun ends in a high vowel with L tone, “ari” changes to rising tone
Why?
Consider ti + ari = tyari. The inital tones are
Code: Select all
L H H
| | |
ti a ri
Code: Select all
L H H
\| |
tya ri
These principles can be used to decide on tone sandhi in a conlang. Decide on the restrictions on tone structure - only one tone per vowel, no toneless vowels, etc. One vowel can only take one tone, so contour tones must be on diphthongs or long vowels only. Whatever seems logical. Then you can apply the rightward drift to get tone interactions in the final words.
This way you can devise systems where the morphemes only have level tones, but the finished words have more complicated contur tones [due to drifitng like in the Margi example].
More interesting bits - Floating Tones and Wordless Tones
Because of this drfiting tendency of tones, some languages have tones that float off on to the next word, and even tones that do not belong to any word. They are a morpheme in their own right:
In San Miguel El Grande Mixtec of Mexico, some nouns
have a suffixal High tone which is underlyingly unassociated. This tone shows its
effects on the following word, if one is present.
• The same pattern occurs with Lango of Uganda.
• In Kalam Kohistani of Pakistan, some words cause a Low tone to occur on the
following word
• In Usarufa of Papua New Guinea, tones set afloat by vowel
deletion in noun phrases manifest themselves on the following word.
An example of a suffixal high tone: In Konni [another African language that sounds like it’s a woman]. In possessive/genitive constructions - such as “my hat, the cat’s tail” the word order is the same as English “possessor + possessed.” When the possessor is a third person noun or pronoun, the possessed object always has a H tone on it’s first syllable.
This can be analysed as their being a H tone suffixed to the end of the possessive form of the third person noun:
Code: Select all
L H L H H
| | | | |
u bua
his/her child’s