Photo taken on Feb. 24, 2021 shows U.S. flag and Texas flag lowered to half-staff in front of Riddle Elementary School in Plano, northern suburban city of Dallas, Texas, the United States. The United States reached the grim milestone of half a million coronavirus deaths on Monday, according to the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University. U.S. President Joe Biden has ordered all U.S. flags to be flown at half-staff for five days at all federal buildings and military posts in the United States and abroad. (Photo by Dan Tian/Xinhua)
