What this means for learners
GUGU-YALANDYI and Ket share 4 sounds — roughly 13% of Ket's inventory overlaps with GUGU-YALANDYI. Shared sounds are ones a speaker already knows from their native language and will generally produce and perceive accurately without explicit training.
The 28 sounds found only in Ket represent the greatest pronunciation challenge for GUGU-YALANDYI 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, GUGU-YALANDYI has 12 sounds not used in Ket. Native Ket speakers learning GUGU-YALANDYI 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.