the highest building in the world-世界最高的高楼

Burj Khalifa 

(Arabic: برج خليفة‎ "Khalifa Tower"), known as Burj Dubai prior to its inauguration, is a skyscraper in Dubai, United Arab Emirates, and the tallest man-made structure ever built, at 828 m (2,717 ft). 

Construction began on 21 September 2004, with the exterior of the structure completed on 1 October 2009.

web site