The French language as it exists today is the result of a long and complex evolution. Ancient France saw many periods of invasion by different ethnic and linguistic groups: Greeks, Romans, Celts, Franks and other Germanic tribes, and Arabs. The most profound influence was exerted by the Romans and their language: Latin. But over the years, as different peoples entered the country, the words and grammatical structures deriving from Latin evolved to fit the needs and patterns of the developing language. Two examples: the Latin for "farmer" was "agricola"; the French is now "agriculteur." The Latin for "are" (they are) was "sunt"; in French, the word has become "sont."
The name, France, actually comes from the name of the Germanic tribe, the Franks, who entered France during late antiquity and gradually became the dominant people. They adopted the late form of Latin being spoken in the country at the time, but added many of their own words, or they changed some of the Latin forms to resemble their own more closely.
A French person today could not understand the early forms of French spoken before the 12th century or so without specialized study.
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