阅读下面的文字后，你会发现原来“胡同”这个名称跟蒙古语有关，本意为“水井”。 (来源：专业英语学习网站 http://www.EnglishCN.com)
Hutongs are narrow streets or alleys, most commonly associated with Beijing, China.
The word hutong comes from the Mongolian hottog meaning "water well." During the growth of towns and cities, wells dug by villagers formed the centres of new communities.
In Beijing, hutongs are alleys formed by lines of siheyuan, traditional courtyard residences. Many neighbourhoods were formed by joining one siheyuan to another to form a hutong, and then joining one hutong to another. The word hutong is also used to refer to such neighbourhoods.
In old China, streets and lanes were defined by width. Hutongs were lanes no wider than 9 metres. Many are smaller; Beijing hutongs range in width from 10 metres down to only 40 centimetres.
Since the mid-20th century, the number of Beijing hutongs has dropped dramatically as they are demolished to make way for new roads and buildings. More recently, some hutongs have been designated as protected areas in an attempt to preserve this aspect of Chinese cultural history.