This class includes nouns which make their plural by taking ma – before the singular. This includes all nouns whose singular prefix is i – or li -. 
Examples:
Ilibwa – Malibwa: cassava
Itabazi – Matabazi: branch
Izina – Mazina: name
Ibele: breast Mabele: woman’s milk 
Ishinde – Mashinde: clod of earth 
Inasi: a blade of grass 
Manasi: herbs 
Igi – Magi: egg
Igambo – Magambo: lyrics 
Itutu – Matutu: leaf 
Irunde: sky, heavens 
Marunde: clouds

The a in ma is contracted into long i Lino – 
Mino: tooth 
Ligwa – Migwa: thorn 
Linsozi – Minsozi: tear 
Lina – Mina: pit 
Ligi – Migi: door

Ly before the vowel a becomes ma Examples: 
Lyato – Mato: boat 
Lyande – Mande: furrow 
Lyambaliro – Mambaliro: costume 
Lyala – Mala: nail Lyale – Male: reel 

Ly – before the vowel o becomes mo
Examples: 
Lyonshi – Monshi: smoke 
Lyolo – Molo: stretched wood 
Lyola – Mola: toad
Lyoma – Moma: ravine

Some instrument names 
Examples: 
Lihyo – Mihyo: sickle 
Isekuzyo – Masekuzyo: pillon 
Ikeshyo – Makeshyo: kind of knife 
Ikoshyo – Makoshyo: chisel 

All nouns whose singular prefix is bu – . Most are action nouns, some are plural, others not. Some do not have a singular.

Examples: 
Buhumbe – Mahumbe or Mabuhumbe: imbecility 
Bushinzi – Mashinzi or Mabushinzi: insomnia 
Bukolwa – Makolwa or Mabukolwa: drunkenness 
Bulozi – Malozi or Mabulozi: witchcraft 
Bugondo – Mabugondo: body 
Bukonde – Mabukonde: sweetness 
Bwato – Mabwato: trough 
Bwenge – Mabwenge: spirit, intelligence 
Bwire – Mabwire: night 
Bwiru – Mabwiru: slavery 
Bula – Mabula: entrails 
Bugoro – Mabugoro: snuff 
Bwami – Mabwami: royalty 
Bwangu – Mabwangu: speed 
Bwira – Mabwira: mercy 
Buyanda – Mabuyanda: childhood Mate: saliva 
Minzi: water 
Magazi: blood 

All augmentative nouns 
Examples: 
Limuti – Mamiti: big tree 
Lishisaka – Mavisaka or Mashisaka: large batch 
Lilukekera – Malukekera or Mankekera: large enclosure 
Lishigulu – Mashigulu or Mavigulu: large termite mound 
Lintu – Mantu: great man 
Lishisabo – Mashisabo or Mavisabo: large calabash 
Limwembi – Mamyambi: an arrow 
Lilugembe – Malugembe or Manyembe: great razor 
Ligulu – Malugulu or Mangulu: large mountain

All names start with na – or n-. Most are animal or bird names, to indicate a large quantity. 
Examples: 
Nahungulema – Manangulema: bat 
Nole – Manole: lizard 
Ngiri – Magiri: wild boar 
Ndulu – Madulu: wild donkey 
Ntinga – Matinga: green pigeon 
Mpera – Mapera: rhinoceros 

Disease names starting with n – or ka-. 
Examples:
Ndubi – Mandubi (not Madubi): smallpox 
Nsefu – Masefu (not Mansefu): hiccups 
Nsundo – Masundo or Mansundo: wart 
Kaswende – Makaswende: syphilis 
Kasoni – Makasoni: bad side 
Kahoha – Makahoha: bronchitis 

Certain words express the action of the verb 
Examples: 
Mazyana: departure, going 
Malevuka: the return 

Nouns expressing the thing or state resulting from the action of the verb
Igambo – Magambo: word, story
Ilagiro – Malagiro: order 
Ipatano – Mapatano: contract 
Iyombo – Mayombo: dispute
Ikugono – Makugono: work