What this means for learners
Nupe and Tiv share 30 sounds — roughly 75% of Tiv's inventory overlaps with Nupe. Shared sounds are ones a speaker already knows from their native language and will generally produce and perceive accurately without explicit training.
The 10 sounds found only in Tiv represent the greatest pronunciation challenge for Nupe 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, Nupe has 8 sounds not used in Tiv. Native Tiv speakers learning Nupe 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.