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.
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Question: The kilogram is the base unit of mass in the International System of Units ( SI ) .

Answer: The kilogram ( also kilogramme ) is the base unit of mass in the metric system , formally the International System of Units ( SI ) , having the unit symbol kg .


Question: Spiritualism is a belief that humans can communicate with the spirits of the dead .

Answer: Spiritualism is a religious movement based on the belief that the spirits of the dead exist and have both the ability and the inclination to communicate with the living .


Question: Many predatory mammals have claws that can hide inside the animal 's paw , especially animals such as the cat .

Answer:
Many predatory mammals have protractile claws that can partially hide inside the animal 's paw , especially the cat family , Felidae , almost all of whose members have fully protractible claws .