What this means for learners
Awadhi and Lahu share 17 sounds — roughly 37% of Lahu's inventory overlaps with Awadhi. Shared sounds are ones a speaker already knows from their native language and will generally produce and perceive accurately without explicit training.
The 29 sounds found only in Lahu represent the greatest pronunciation challenge for Awadhi 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, Awadhi has 28 sounds not used in Lahu. Native Lahu speakers learning Awadhi 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.