Answer:
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The Neolithic Revolution, also called the Agrarian Revolution, was the change from a nomadic, hunter-gatherer lifestyle to a settled, agrarian one with farming. Farming is more stable and secure and it gives people more time to engage in other activities, such as improving their tools and developing cultures: the Neolithic Revolution contributed to the technological development in the river valley civilizations by giving people time to improve on their technology.
Talking to a person you do not know, an email to a business representative, and similar would be situations where someone would have to use formal language.
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