reporters abroad may file their stories in toneless pinyin. Dungan, a variety of Mandarin Chinese spoken in Central Asia, has, since 1927, been written in orthographies that do not indicate tone. Ndjuka, in which tone is less important, ignores tone except for a negative marker. However, the reverse is also true: in the Congo, there have been complaints from readers that newspapers written in orthographies without tone marking are insufficiently legible. Standard Central Thai has five tones–mid, low, falling, high and rising–often indicated respectively by the numbers zero, one, two, three and four. The Thai alphabet is an alphasyllabary, which specifies the tone unambiguously. Tone is indicated by an interaction of the initial consonant of a syllable, the vowel length, the final consonant (if present), and sometimes a tone mark. A particular tone mark may denote different tones depending on the initial consonant. The Shan alphabet, derived from the Burmese script, has five tone letters: , , , , ; a sixth tone is unmarked. Vietnamese uses the Latin alphabet and its six tones are marked by letters with diacritics above or below a certain vowel. Basic notation for Vietnamese tones are as follows: The Latin-based Hmong and Iu Mien alphabets use full letters for tones. In Hmong, one of the eight tones (the tone) is left unwritten while the other seven are indicated by the letters b, m, d, j, v, s, g at the end of the syllable. Since Hmong has no phonemic syllable-final consonants, there is no ambiguity. That system enables Hmong speakers to type their language with an ordinary Latin-letter keyboard without having to resort to diacritics. In the Iu Mien, the letters v, c, h, x, z indicate tones but unlike Hmong, it also has final consonants written before the tone. The Standard Zhuang and Zhuang languages used to use a unique set of six "tone letters" based on the shapes of numbers, but slightly modified, to depict what tone a syllable was in. This was replaced in 1982 with the use of normal letters in the same manner, like Hmong. The syllabary of the Nuosu language depicts tone in a unique manner, having separate glyphs for each tone other than for the mid-rising tone, which is denoted by the addition of a diacritic. Take the difference between ꉬ nge [ŋɯ³³] , and ꉫ ngex [ŋɯ³⁴]. In romanisation, the letters t, x, and p are