Some of the problems that (41) people in the U.S. (42) in the cities during old days are still (43) us -- poor planning, problems in (44) neighborhoods, and public transportation.
(45) was a very important for city governments in the last century, (46) regard to water supplies, it was known that water could be polluted, (47) they didn’t know (48) . Trying to get pure water was a big problem.
People like to talk about the (49) old days, but actually, the cities of the 19th century were dirty and, (50) , filthier than today. (51) disease was a great (52) . There was still smallpox(天花) and also yellow fever and malaria. The (53) death rate was high, and there were other dangers as well.
(54) true that people were not being killed by cars. (55) , they often were killed or seriously (56) by runaway horses. It was quite common.
Planning o
A. were living
B. being living
C. lived
D. living
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