What this means for learners
Telefol and Luganda share 21 sounds — roughly 64% of Luganda's inventory overlaps with Telefol. Shared sounds are ones a speaker already knows from their native language and will generally produce and perceive accurately without explicit training.
The 12 sounds found only in Luganda represent the greatest pronunciation challenge for Telefol 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, Telefol has 6 sounds not used in Luganda. Native Luganda speakers learning Telefol 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.