When a foreign writing system with one set of sounds and coding/decoding system is taken to write one's own language, certain compromises must be made. The result is that the decoding systems used in some foreign languages will enable non-native speakers to produce sounds more closely resembling the target language than will the coding/decoding system used by other foreign languages. Native speakers of English will decode pinyin spellings to fairly close approximations of Mandarin except in the case of certain speech sounds that are not ordinarily produced by most native speakers of English: j, q, x, z, c, s, zh, ch, sh, and r exhibiting the greatest discrepancies. (When Chinese speakers call out these letters, they read them as: ji, qi, xi, zi, ci, si zhi, chi, shi, and ri. The "i" in the last four sounds more like "r" and the use of "i" is purely a matter of convention.) More information on how to produce these sounds will be given below.
In this system, the correspondence between the Roman letter and the sound is sometimes idiosyncratic, though not necessarily more so than the way the Latin script is employed in other languages. For example, the aspiration distinction between b, d, g and p, t, k is similar to that of English (in which the two sets are however also differentiated by voicing), but not to that of French. Z and c also have that distinction, pronounced as and, both similar to German and Italian, which however do not have the distinction. From s, z, c come the digraphs sh, zh, ch by analogy with English sh, ch. Although this introduces the novel combination zh, it is internally consistent in how the two series are related, and reminds the trained reader that many Chinese pronounce sh, zh, ch as s, z, c (and English-speakers use zh to represent /ʒ/ in foreign languages such as Russian anyway). In the x, j, q series, the Pinyin use of x is similar to its use in Portuguese, Galician, Catalan, Basque and Maltese; and the Pinyin q is akin to its value in Albanian; both Pinyin and Albanian pronunciations may sound similar to the ch to the untrained ear. Pinyin vowels are pronounced in a similar way to vowels in Romance languages. More information on the pronunciation of all pinyin letters in terms of English approximations is given further below.
The pronunciation and spelling of Chinese words are generally given in terms of initials and finals, which represent the segmental phonemic portion of the language, rather than letter by letter. Initials are initial consonants, while finals are all possible combinations of medials (semivowels coming before the vowel), the nucleus vowel, and coda (final vowel or consonant).
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