Answer:
If you're talking about the myth where she is stolen by Hades, she is returned on the condition she split her time between Demeter and Hades. In some versions, she spends spring and summer with her mom and fall and winter with Hades, and in others, she spends 3/4 of the year with Hades and 1/4 of her year with Demeter.
Step-by-step explanation: