Universal 1247:

Original: If tone spreading takes place from a mid tone into a following low, then tone spreading also takes place from a high tone into a following low tone.
Standardized: IF tone spreading takes place from a mid tone into a following low, THEN tone spreading also takes place from a high tone into a following low tone.
Keywords: tone, tone spreading
Domain: prosodic phonology
Type: implication
Status: achronic
Quality: absolute
Basis: West African languages: Bolanci, Ga?anda, Hausa, Kanakuru (=Dera), Ngizim (all Chadic); Etsako (Edoid); Ewe, Twi (both Kwa); Gwari, Igbirra, Nupe (all Nupoid); Igbo (Igboid); Yoruba (Defoid); Fe?fe?, Kikuyu, Kinga, Mbui, Safwa, Sukuma, Tigong, Xhosa, Zulu (all Bantu); Kpelle, Mende (both Mande).
Source: Hyman & Schuh 1972: 14 (Hyman & Schuh 1972[1974]: 89)

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