A.Health. | B.Technology. |
C.Entertainment. | D.Business. |
A.introduce the main topic |
B.expose a social problem |
C. show sympathy to the elderly |
D. arouse medical workers' interest |
A.②③⑤ | B.①④⑥ |
C.③④⑤ | D.①②⑤ |
A.the system should reduce its cost |
B.smart cities should be human-based |
C.mass production is still impossible |
D.individuals are responsible for future |