求翻译：据调查，至今中国已有90多个城市和地区发生不同程度的地面沉降，最为突出的是以上海为代表的长江三角洲、以天津为代表的环渤海区和西安等地。是什么意思？

According to the survey, so far China has more than 90 cities and regions have varying degrees of ground settlement occurred, most notably with Shanghai as the representative of the Yangtze River Delta, as represented by the Tianjin Bohai area and Xian and other places.

According to a survey, so far China has more than 90 cities and regions in different degrees of surface subsidence, most prominently, the Yangtze River to Shanghai as a representative of the Delta 3, with a view to Tianjin for the Bohai area representative and Xi'an.

According to the investigation, China had more than 90 cities and the area until now has the varying degree surface subsidence, most prominent is take Shanghai as representative's Yangtze River delta, take Tianjin as places such as representative's link Bohai Sea area and Xi'an.

According to the survey, so far China has more than 90 cities and regions have varying degrees of ground settlement occurred, most notably with Shanghai as the representative of the Yangtze River Delta, as represented by the Tianjin Bohai area and Xian and other places.

正在翻译，请等待...