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.

Input: Consider Input: A head teacher ( also called a school principal , or headmaster / headmistress ) is the teacher in charge of a school .

Output: A head teacher , headmaster , headmistress , head , chancellor , principal or school director ( sometimes another title is used ) is the staff member of a school with the greatest responsibility for the management of the school .


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

Output: 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 .


Input: Consider Input: Oxygen saturation or dissolved oxygen ( DO ) is a relative measure of the amount of oxygen that is dissolved in a given medium .


Output: Oxygen saturation ( symbol S ) is a relative measure of the concentration of oxygen that is dissolved or carried in a given medium as a proportion of the maximal concentration that can be dissolved in that medium .