Yam (vegetable) Yam (vegetable) Yam is the common name for some plant species in the genus "Dioscorea" (family Dioscoreaceae) that form edible tubers. Yams are perennial herbaceous vines cultivated for the consumption of their starchy tubers in many temperate and tropical world regions. The tubers themselves are also called "yams", having numerous cultivars and related species. In parts of the United States and Canada, "yam" is sometimes used to refer to varieties of the unrelated sweet potato ("Ipomoea batatas"). The name, yam, appears to derive from Portuguese "inhame" or Canarian (Spain) "ñame", which derived from West African languages during trade. The main
Varieties of Chinese the tone categories of Middle Chinese, but in Shanghainese several of these have merged. Many Chinese varieties exhibit tone sandhi, in which the realization of a tone varies depending on the context of the syllable. For example, in Standard Chinese a third tone changes to a second tone when followed by another third tone. Particularly complex sandhi patterns are found in Wu dialects and coastal Min dialects. In Shanghainese, the tone of all syllables in a word is determined by the tone of the first, so that Shanghainese has word rather than syllable tone. Most morphemes in Chinese varieties are