Tommo So is a language spoken in the eastern part of Mali's Mopti Region.

Bambara and French (Mali's lingua franca and national language) are common second languages for Tommo So speakers, with the former being common among those that have spent time in other areas of Mali, and the latter being used to communicate in the classroom or with foreigners.

The nasalized vowels /iːn/ and /uːn/ are present in the language but occur infrequently and irregularly, and are not considered phonemic.

However, these sounds occur only in ideophones, and are not considered part of Tommo So's consonant inventory.

[10] There are eight syllable types in Tommo So: (C)V, (C)Vː (C)VR, (C)VC, N, NCV, NCVː, and CVV.

[12] Based on an analysis of recorded words, the distribution and placement of H and L tones seem to be governed by a set of patterns that are relatively unpredictable for nouns, numerals, and adjectives, and predictable for verbs.

In general, when these morphemes are attached to each other, they retain their original form and meaning within the new word.

As an agglutinative language, the affixation of morphemes plays a major role in Tommo So's morphology.

Almost all of the language's bound morphemes are used as suffixes—prefixes are only seen in the form of reduplication, when used for deadjectival nominalization.

[19] FACT:factitive REV:reversive MP:mediopassive yɛ̀see'see'→  yɛ̀-ndɛ́see-FACT'watch'[20]  yɛ̀ → yɛ̀-ndɛ́see {} see-FACT'see' {} 'watch'dɛ̀bɛ́get stuck'get stuck'→  dɛ̀b-ílɛ́get stuck-REV'get unstuck'[21]  dɛ̀bɛ́ → dɛ̀b-ílɛ́{get stuck} {} {get stuck}-REV{'get stuck'} {} {'get unstuck'}pɛ́ndɛ́make tight'make tight'→  pɛ́nd-íyɛ́make tight-MP'get crowded'[22]  pɛ́ndɛ́ → pɛ́nd-íyɛ́{make tight} {} {make tight}-MP{'make tight'} {} {'get crowded'}There are some cases in which the 'reversive' suffix -ílɛ́ does not seem to contain a reversive meaning.

yàá-m=mbefemale-HUM.PL=PLyàá-m=mbefemale-HUM.PL=PL'women'yàà-mfemale-HUM.PLkómmó=gɛ=mbeskinny=def=PLyàà-m kómmó=gɛ=mbefemale-HUM.PL skinny=def=PL'the skinny women'In general, clitics are always attached to the end of a stem, and never the beginning.

nɛ̀msalttáádoor[29] nɛ̀m táásalt door'slab of salt'bòmbòmcandyyòògúsap[30] bòmbòm yòògúcandy sap'chewing gum'hɔ̀ɔ̀làltrustbàŋááowner[31] hɔ̀ɔ̀làl bàŋáátrust owner'trustworthiness'Bahuvrihi compounding in Tommo So occurs when a complex noun is created by attaching an adjective to the end of a noun.

ǹdɛ̀personáŋámouthwɛ̂ylight[32] ǹdɛ̀ áŋá wɛ̂yperson mouth light'gossipy person'àn-nà-ymale-HUM.SG-DIMdɔ́lɔ́testiclepóòfat[32] àn-nà-y dɔ́lɔ́ póòmale-HUM.SG-DIM testicle fat'boy with large testicles'Tommo So's basic word order is subject-object-verb (SOV).