This paper compares approximants with continuants, semivowels, fricatives, liquids, and vowels, and identifies the initial ri in Mandarin as an approximant rather than a voiced fricative.
本文比较了近音与通音、半元音、擦音、流音、元音之间的异同，认定普通话日母是近音而非浊擦音。
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The railway dispatching telephone system may be treated as a ladder network, its transmission characteristics can be precisely analysed and calculated by continuants (one kind of determinants).