What this means for learners
Guarani and Lak share 11 sounds — roughly 16% of Lak's inventory overlaps with Guarani. Shared sounds are ones a speaker already knows from their native language and will generally produce and perceive accurately without explicit training.
The 58 sounds found only in Lak represent the greatest pronunciation challenge for Guarani 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, Guarani has 25 sounds not used in Lak. Native Lak speakers learning Guarani 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.