What phrase is repeated in this passage?

What idea is given. importance through the use of repetition in this passage?

the foundation of greek city-states: following the fall of the mycenaean civilization in the 10th century bc, the area surrounding the empire went through its own mini dark ages. answer and explanation

copernicus finished the first manuscript of his book, "de revolutionibus orbium coelestium" ("on the revolutions of the heavenly spheres") in 1532. in it, copernicus established that the planets orbited the sun rather than the earth. he laid out his model of the solar system and the path of the planets.

the eop relieves the president of the duty of serving as commander in chief. the also eop reduces the president's ability to appoint staff and advisers.

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