Classes 3 and 4 pair singular m-/mw- with plural mi-. They contain many trees and plants—mti/miti “tree/trees,” mnazi/minazi “coconut palm(s)”—as well as natural features, body parts, long objects, periods of time, and other inherited vocabulary. Their agreement contrast is singular u- versus plural i- on the verb.
That verbal contrast matters because class 3 nouns look deceptively like class 1 human nouns. Mti “tree” and mtu “person” both begin with m-, and both can take an adjective such as mrefu. Their plurals and wider concords reveal the difference: mti huu umeanguka/miti hii imeanguka versus mtu huyu ameanguka/watu hawa wameanguka. The forms on this page are neutral Standard Swahili.
Forming the m-/mi- pair
Before a consonant, singular nouns normally show m-; before a vowel-initial stem, the noun often shows mw-. The plural normally has mi-, with changes at the vowel boundary in some common nouns.
| Singular | Plural | Meaning | Semantic tendency |
|---|---|---|---|
| mti | miti | tree / trees | plant |
| mnazi | minazi | coconut palm(s) | plant |
| mto | mito | river(s) | natural feature |
| mlima | milima | mountain(s), hill(s) | natural feature |
| mkono | mikono | arm(s), hand(s) | body part |
| mwiko | miiko | cooking stick(s), serving spoon(s) | long object |
| mwaka | miaka | year(s) | period of time |
“Trees and long things” is a useful memory aid, not a definition. Mto is a river, mji/miji means “town/towns,” and mwaka/miaka expresses time. Conversely, not every tree part or elongated object belongs here. You still need to learn the singular and plural together.
The competing human m- pattern is presented on classes 1/2: m-/wa- human nouns.
The core concords
Class 3 and class 4 do not copy the noun prefixes across every word. They have their own subject, demonstrative, and possessive forms.
| Agreement family | Class 3 singular | Class 4 plural |
|---|---|---|
| Subject marker | u- | i- |
| Object marker | u- | i- |
| Adjective concord | m-/mw- | mi- |
| “this / these” | huu | hii |
| referential “that / those” | huo | hiyo |
| distant “that / those over there” | ule | ile |
| Possessive concord | w- | y- |
Thus u-me-anguk-a becomes the normal written word umeanguka, while plural i-me-anguk-a becomes imeanguka. Hyphens belong only in the analysis, never inside the ordinary finite verb.
Following mti and miti
The pair mti/miti displays every central contrast clearly. Adjective -refu takes m-/mi-; “this/these” is huu/hii; “my” is wangu/yangu; and the verb begins with u-/i-.
Mti huu mrefu ni wangu, na umeanza kutoa maua.
This tall tree is mine, and it has begun to flower.
Miti hii mirefu ni yangu, na imeanza kutoa maua.
These tall trees are mine, and they have begun to flower.
English lets “my” and “tall” remain unchanged. Swahili marks the number-class contrast on both. Notice that plural miti does not take wa- merely because English translates the verb with “they.” Nonhuman plural “they” is expressed through the noun’s own class, here i-.
Mti huo mzuri umeanguka baada ya mvua kubwa.
That beautiful tree fell after the heavy rain.
Miti hiyo mizuri imeanguka baada ya mvua kubwa.
Those beautiful trees fell after the heavy rain.
The subject markers are small, but they are grammatically decisive. Umeanguka points back to one class 3 subject; imeanguka points back to a class 4 subject.
Following mto and mito
The river pair shows that the class is not limited to plants. With -pana “wide,” the adjective is mpana/mipana. With the first-person plural possessive stem -etu, the forms are wetu/yetu.
Mto wetu huu mpana unapita karibu na kijiji.
This wide river of ours passes near the village.
Mito yetu hii mipana inapita karibu na vijiji kadhaa.
These wide rivers of ours pass near several villages.
In normal discourse, speakers often use fewer modifiers: Mto huu unapita karibu na kijiji is perfectly complete. The expanded examples make the agreement chain visible. They do not establish a requirement to repeat class marking wherever optional words could be added.
Mto huo umefurika, kwa hiyo daraja limefungwa.
That river has flooded, so the bridge has been closed.
Mito hiyo imefurika baada ya mvua ya siku tatu.
Those rivers have flooded after three days of rain.
The deceptive surface forms
The most important trap is singular m-. A person and a tree may even use the same adjective form:
Mtu huyu mrefu amesimama karibu na mti huu mrefu.
This tall person is standing near this tall tree.
The demonstratives make the classes audible: huyu for the person, huu for the tree. The verbs would be amesimama for class 1 and umesimama for class 3. In the plural the contrast expands to watu hawa warefu versus miti hii mirefu.
Vowel-initial stems can also hide the neat segmentation. Mwiko/miiko and mwaka/miaka do not form their plural by replacing the letters mw with the written string miw. Learn the finished lexical pairs and let their concords remain regular.
Mwiko huu mrefu ni wangu; miiko hii mifupi ni yako.
This long cooking stick is mine; these short ones are yours.
The plural noun miiko controls hii, mifupi, and i- if used as a verbal subject. Surface spelling can change at a vowel boundary without changing the underlying class pairing.
Common Mistakes
Using human subject agreement with an ordinary class 3 noun
❌ Mti anaanguka.
Incorrect — class 3 uses the subject marker u-.
✅ Mti unaanguka.
The tree is falling.
Using the human demonstrative because the noun begins with m-
❌ Mto huyu umefurika.
Incorrect — mto is class 3 and takes huu.
✅ Mto huu umefurika.
This river has flooded.
Changing only the noun in the plural
❌ Miti huu mrefu umeanguka.
Incorrect — all the agreeing words remain class 3 singular.
✅ Miti hii mirefu imeanguka.
These tall trees have fallen.
Copying mi- onto the possessive
❌ Miti miangu imekauka.
Incorrect — the class 4 possessive concord is y-, giving yangu.
✅ Miti yangu imekauka.
My trees have dried up.
Assuming every tree-related noun must be class 3/4
❌ Tawi huu umevunjika.
Incorrect — tawi branch is class 5, despite its plant-related meaning.
✅ Tawi hili limevunjika.
This branch has broken.
Key Takeaways
- Class 3/4 usually pairs singular m-/mw- with plural mi-.
- Its core agreement contrast is u-, huu, w- in the singular versus i-, hii, y- in the plural.
- The initial m- does not distinguish class 3 from human class 1; plural and concord do.
- Trees and long or natural things are tendencies, not an exceptionless semantic rule.
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Start learning Swahili →Related Topics
- Classes 1a/2a: Prefixless Human and Kinship NounsA2 — Understand human and kinship nouns such as baba, mama, and kaka whose noun form lacks m- but whose core agreement is human.
- Classes 5/6: ji-/ma- NounsA1 — Learn the often-zero or ji- class 5 singular, the productive ma- class 6 plural, and their li-/ya- agreement.
- M- Means Two Things: Class 1 or Class 3A2 — Distinguish human class 1 m-/wa- nouns from class 3 m-/mi- nouns by plural formation, meaning, and agreement.
- Plants and Natural Objects in Classes 3/4A2 — Recognize the strong plant and natural-feature tendency in classes 3/4 while using plural forms and U-I agreement to identify real membership.