mirongwibiri   adj    twenty
umurōngo (imi-)     2  class 2
singular: umu-
plural: imi-
  
1. row, 2. line, 3. alignment, 4. verse, 5. (pl.) mirongo multiples of ten
mirongwibiri, -tatu, etc. 20, 30, etc.
twenty    mirongwibiri
En-En dictionary 
 mirongwibiri found in: Kirundi I (Study lessons)
lesson 38   Higher Numbers
lesson 62   Months, Days of the Week, Telling Time