With the development of the economy and society, many countries are challenged with an aging population. According to China's seventh national census, its population aged 65 or above accounts for 13.5 percent of the total. The country has an arduous task to cope with an aging society. So what has China done to ensure a comfortable life for the elderly? What are the characteristics of China's elderly pension and care system? In this episode of "The Tough Question," Professor Dong Keyong from the School of Social Sciences at Tsinghua University shares his thoughts.