lacking    (to be) guhara, gusība
En-En dictionary 
guhara (-haze)     v    1. to scrape, 2. damage, 3. to tan hides, 4. to yelp, 5. purr, 6. to be lacking (usually stative), to be incomplete
soft    (anything very ~, lacking stiffness) urudēndevu
(to be) kwōroha
(to be silky ~) kurēmba
(to get ~ in water) kubōmbōka
(to make soil ~) kwōrohereza
(and springy, e.g. earth in swamp) kudemwademwa
En-En dictionary 
gusība (-sīvye)     v    1. to be absent, 2. to miss, to be short (lacking), 3. to abstain
ukubura   9  class 9
singular: uku-
  
lacking, absence
urudēndevu (in-)     6  class 6
singular: uru-
plural: in-
  
weak, faltering person, anything very soft (lacking stiffness)
 lacking found in: Kirundi I (Study lessons)
lesson 62   Months, Days of the Week, Telling Time
 lacking found in: Kirundi II (Grammar)
chapter 75   Colours