    Sentence 1: The U.S. military on Dec. 2 began a  large-scale sweep , dubbed Operation Avalanche ,  targeting the south and east of the country , where  Taliban activity has been highest 3.    Sentence 2: Since Dec. 2 the U.S. military has been  engaged in a large-scale sweep , dubbed Operation  Avalanche _, targeting the south and_east_of the  country          