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

SOLUTION: 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 .

PROBLEM: Since 1964 , athletes of the Congo have taken part in the " Olympic Movement " .

SOLUTION: The Republic of the Congo , competing as Congo , first participated at the Olympic Games in 1964 , and has sent athletes to compete in most Summer Olympic Games since then .

PROBLEM: The parasympathetic nervous system ( PNS or PSNS ) is part of the autonomic nervous system .

SOLUTION:
The parasympathetic nervous system ( PSNS ) is one of the two divisions of the autonomic nervous system ( a division of the peripheral nervous system ( PNS ) ) , the other being the sympathetic nervous system .