<Li> Northerners speak with a higher - pitched accent and frequently pronounce words with a / z / (even though the letter <z> doesn't exist in the Vietnamese Latin alphabet). </Li> <Li> Central Vietnamese (in the North - Central Coast, from Nghệ An to Thừa Thiên - Huế) speak in a more lower - pitched, more monotone accent, which is also found in the accents of various aboriginal languages spoken by Montagnard hill tribe ethnicities, for example in the A Sầu Valley - A Lưới . </Li> <Li> Southerners, along with the South Central Coast provinces of Bình Định, Phú Yên, Khánh Hòa, Ninh Thuận and Bình Thuận, speak with no significantly distinctive accent; metaphorically, it is similar to American English (excl . the Southern and New York City dialects). Some remark the Southern Vietnamese accent (in Nam Kỳ Lục tỉnh) is similar to Khmer . </Li> <P> Because the accents of Central Vietnam (culturally centered at the ancient capital of Huế), to the unaccustomed ear, reduce the number of tones to 5 (for Quảng Trị and Huế accents) or only 4 (for Hà Tĩnh, Nghệ An and Quảng Bình accents), Central Vietnamese speech can be relatively difficult to understand for Vietnamese speakers from the Northern and Southern regions . The most difficult are from the provinces of Nghệ An and Hà Tĩnh . </P>

Why did north vietnam and south vietnam split