Question of the Week: Raqueeb Shaik from Al-Jubail, Saudi-Arabia - Why do we sleep? - Tomorrow Today 26.05.2008To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 videoMilan Tillich05/26/2008May 26, 2008Why do we sleep?https://p.dw.com/p/E64fAdvertisement