Queen Sofia of Spain (C) holds a giant panda doll during an agreement signing ceremony at the Zoo Aquarium in Madrid, Spain, Feb. 23, 2018. With the agreement, three giant pandas, which have been kept in Zoo Aquarium in Madrid, will stay in the zoo for another five years until 2023. The year of 2018 is the 40th anniversary of the first arrival of Chinese giant pandas to Spain. (Xinhua/Guo Qiuda)