What this means for learners
Selepet and Kikuyu share 15 sounds — roughly 47% of Kikuyu's inventory overlaps with Selepet. Shared sounds are ones a speaker already knows from their native language and will generally produce and perceive accurately without explicit training.
The 17 sounds found only in Kikuyu represent the greatest pronunciation challenge for Selepet speakers. The adult brain tends to map unfamiliar sounds onto the closest native equivalent — a process that produces the characteristic "accent" of a second-language speaker. Learning to hear and produce these sounds as distinct requires focused ear training, not just repetition.
Conversely, Selepet has 6 sounds not used in Kikuyu. Native Kikuyu speakers learning Selepet will face the mirror-image challenge with these sounds.
Phoneme inventories from PHOIBLE. Data reflects one documented inventory per language; some variation exists across dialects and sources.