What this means for learners
Mapudungun and Kimeru share 18 sounds — roughly 64% of Kimeru's inventory overlaps with Mapudungun. Shared sounds are ones a speaker already knows from their native language and will generally produce and perceive accurately without explicit training.
The 9 sounds found only in Kimeru represent the greatest pronunciation challenge for Mapudungun 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, Mapudungun has 10 sounds not used in Kimeru. Native Kimeru speakers learning Mapudungun 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.