In this task, we ask you to elaborate the sentence without changing its general meaning. You can do so by explaining further the input sentence, using more precise wording, adding qualifiers and auxiliary information etc.

Q: They give their permission through their elected representatives ( Rule by the People ) , who is the source of all political power .

A: Popular sovereignty is the principle that the authority of a state and its government are created and sustained by the consent of its people , through their elected representatives ( Rule by the People ) , who are the source of all political power .
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Q: Race length can be either a time or a number of laps .

A: Race length can be determined by a number of laps or total time , in which case the number of remaining laps is calculated as the race progresses .
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Q: During the American Civil War , the river , with few convenient fords and fewer bridges , provided a barrier and defensive line .

A:
During the American Civil War , the river , with few convenient fords and fewer bridges , provided a barrier and defensive line behind which movements of troops could be accomplished with little fear of attack from the river-side flank .
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