What this means for learners
Djapu and Lak share 12 sounds — roughly 17% of Lak's inventory overlaps with Djapu. Shared sounds are ones a speaker already knows from their native language and will generally produce and perceive accurately without explicit training.
The 57 sounds found only in Lak represent the greatest pronunciation challenge for Djapu 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, Djapu has 13 sounds not used in Lak. Native Lak speakers learning Djapu 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.