The small xx represents the local language, which is a two letter ISO-639 language code and the capital XX represents the local country, which is a two letter ISO-3166 country code.

小写的xx 表示本地语言，它是一个 ISO-639 语言编代码，为两个字母；大写的 XX 表示本地国家，它是一个 ISO-3166 国家代码，为两个字母。

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Reservationist (r) : Shanghai XX Hotel.Reservation Desk.Can I help you?

上海XX酒店，预订处，有什么需要帮助吗？

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Many workers find themselves saying, "If only I earned $XX, then I would be happy.

许多人都说：“要是我赚了XX美元，我就会快乐”。

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Alas, his uncle has no idea of the right size: small, medium or even XX-large?

ECONOMIST: Johnson

Still, the four BTO gaming rigs unveiled by the latest iteration of Commodore -- the XX, GX, GS, and G -- seem to stand on their own as solid machines, offering anywhere from a 1.86GHz Core 2 Duo E6320 to a 2.66GHz QX6700 Core 2 Extreme CPU, a single NVIDIA GeForce 7900 GS all they way up to dual 8800 GTX cards, between 2GB and 4GB of RAM, and hard drive capacities up to 750GB in an array of RAID configurations.

ENGADGET: Commodore unveils boutique gaming rigs at CeBIT

My books include the novels "Sellout" and "Wink" and several educational titles (subjects varying from drug abuse and its impact on society, a historical look at domestic spying, and a biography of Bill Gates) as well as "Tested XX" - the bestselling history of my rather inbred family, which also happens to be America's oldest family of knife-makers, the infamous Case clan.

FORBES: I seek small stories with big implications.