Evolution and transformation of China's contemporary elderly care service system Evolution and transformation of contemporary Chinese diplomacy Research on the construction of urban community elderly care service system 并列题名：Research on the construction of urban community elderly care service system Research on the construction and policy support of rural elderly care service system 并列题名：Evolution and transformation of contemporary Chinese diplomacy Study on the construction of the Chinese contemporary legal culture system 并列题名：Research on the construction and policy support of rural elderly care service system