Visitors pose for photos at a major exhibition to commemorate the 40th anniversary of China's reform and opening-up at the National Museum of China in Beijing, capital of China, Jan. 5, 2019. Over 2.4 million person-times of visitors have viewed the exhibition since its opening. (Xinhua/Pan Xu)

　　Visitors view a major exhibition to commemorate the 40th anniversary of China's reform and opening-up at the National Museum of China in Beijing, capital of China, Jan. 5, 2019. Over 2.4 million person-times of visitors have viewed the exhibition since its opening. (Xinhua/Pan Xu)

　　Visitors view a major exhibition to commemorate the 40th anniversary of China's reform and opening-up at the National Museum of China in Beijing, capital of China, Jan. 5, 2019. Over 2.4 million person-times of visitors have viewed the exhibition since its opening. (Xinhua/Pan Xu)

　　Visitors view a major exhibition to commemorate the 40th anniversary of China's reform and opening-up at the National Museum of China in Beijing, capital of China, Jan. 5, 2019. Over 2.4 million person-times of visitors have viewed the exhibition since its opening. (Xinhua/Pan Xu)