Prenasalized consonants are phonetic sequences of a nasal and an obstruent (or occasionally a non-nasal sonorant such as ) that behave phonologically like single consonants. The primary reason for considering them to be single consonants, rather than clusters as in English finger or member, lies in their behaviour; however, there may also be phonetic correlates which distinguish prenasalized consonants from clusters. Because of the additional difficulty in both articulation and timing, prenasalized fricatives and sonorants are not as common as prenasalized stops or affricates, and the presence of the former implies the latter. In most languages, when a prenasalized consonant is described as "voiceless", it is only the oral portion that is voiceless, and the nasal portion is modally voiced. Thus, a language may have "voiced" and "voiceless" . However, in some Southern Min (including Taiwanese) dialects, voiced consonants are preceded by voiceless prenasalization: . Yeyi has prenasalized ejectives. Adzera has a . Prenasalized stops may be distinguished from post-stopped nasals (orally released nasals), such as the of Acehnese and similar sounds (including voiceless ) in many dialects of Chinese. (At least in the Chinese case, nasalization, in some dialects, continues in a reduced degree to the vowel, indicating that the consonant is partially denasalized, rather than actually having an oral release.) No language is believed to contrast the two types of consonant, which are distinguished primarily by a difference in timing (a brief nasal followed by longer stop, as opposed to a longer nasal followed by brief stop). Geographic distribution Africa The Bantu languages are famous for their prenasalized stops (the "nt" in "Bantu" is an example), but similar sounds occur across Africa and around the world. Ghana's politician Kwame Nkrumah had a prenasalized stop in his name, as does the capital of Chad, N'Djamena (African prenasalized stops are often written with apostrophes in Latin script transcription although this may sometimes indicate syllabic nasals instead). The sound can also be found in approximately 90 languages in Africa. East Asia In Southern Min languages, such as Teochew, prenasalized stops are also found. The prenasalized stops in the southern Min languages evolved from the nasals of Middle Chinese and thus are historically different from the voiced obstruents found in Wu and Xiang languages. Prenasalized consonants are widely utilized in the Loloish languages of the Lolo–Burmese family, such as Yi and Naxi. The following table illustrates the prenasalized consonants in northern Yi.