Linguistic area in northwest China
The Qinghai–Gansu sprachbund or Amdo sprachbund is a sprachbund in the plateau traversed by the upper Yellow River, including northeastern Qinghai and southern Gansu. This has long been an area of interaction between speakers of northwestern varieties of Mandarin Chinese, Amdo Tibetan and Mongolic and Turkic languages. These families feature contrasting typologies, which spread between languages in the region. The languages have come to share many features, and differ significantly from their relatives outside the region.
Languages.
The languages involved include
More mainstream varieties of northwestern Mandarin are spoken in the provincial capitals, Xining and Lanzhou.
All these languages are subject to a superstrate influence from Standard Mandarin.
These languages belong to families with three sharply contrasting typologies:
The Mandarin varieties have acquired such features as spirantized voiceless stops, SOV word order and case markers.
The Wutun language of Tongren county, Qinghai, is a highly divergent Mandarin variety, with phonological and grammatical structures resembling Amdo Tibetan.
In some cases, the changes progress through the speaker population in a few decades, so that they can be observed in progress.
A common pattern is to add a borrowed structure beside an indigenous structure with the same function, after which the indigenous structure loses its function and eventually disappears, leaving a changed syntactic pattern.
For example, the indigenous Bonan comparative structure was N-"si", where the noun N represents the standard being compared against.
Bonan added the equivalent Mandarin structure, "bi"+N, yielding a composite "bi"+N-"si".
The original suffix was then lost, leaving a transformed syntactic pattern.
References.
Citations.
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Works cited.
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