During the industrial era, us cities quickly became places where
immigrants lived in isolation.
only a few immigrants moved.
immigrants could congregate and support one another.
immigrants could shed their cultures and adopt a new one.

During the industrial era, US cities quickly became places where  immigrants could congregate and support one another.

Explanation:

The industrial revolution was the transition from manual to machine-made goods that has been accompanied by large-scale organizational and social changes.

From an organizational point of view, the factory system meant a completely different way of working. This changed with industrialization and the arrival of capital-intensive machines. Because the means of production were beyond the reach of the workers, labor relations also changed. Labor was carried out as wage labor and the workers lost their independence. Where they could first determine their own work rate, they were now tied to the factory's working hours, which made different demands on the work ethic. Living and working were now also completely separated. The working environment and work rhythm therefore changed drastically with the introduction of the factory system. The system also had a major impact on administrative tasks by organizing office work in a similar manner.  

Everyday life drastically changed where the industrial revolution came. With the arrival of factories, the industry disappeared from the villages. Many villagers went after the labor towards the factories, which greatly increased urbanization. The population remained stable due to the initially high birth rate, but as soon as the demographic transition came to an end, the rural depopulation started. Where people previously followed the rhythm of the days and seasons, they were now bound by the time to coordinate actions or services. Work in factories required little knowledge and skills, so workers became interchangeable.

After several generations, the social issue improved, on the one hand through the formation of unions that enforced shorter working hours, higher salaries and better working conditions, and on the other by the government, which among other things put an end to child labor. Children were no longer a source of income, which reduced the need for offspring. With the introduction of compulsory education, this also meant a major change for women who got more opportunities. Conditions would improve in such a way that people ended up living healthier than before industrialization.

polisit can also mean a body of citizens. in modern historiography, polis is normally used to indicate the ancient greek city-states, like classical athens and its contemporaries, and thus is often translated as "city-state". the body of citizens came to be the most important meaning of the term polis in ancient greece.

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