unroll       
verb [ I or T ] uk/ʌnˈrəʊl/ us/ʌnˈroʊl/
 (使)铺开;(使)展开
to open and become flat from a rolled position, or to cause something to do this
  She unrolled the most beautiful carpet. 她展开了这块精美绝伦的地毯。 
 Synonym: unfurl
Opposite: roll something up