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In this task, you're given an article and an answer. Your task is to generate the fill-in-the-blank question for this answer based on the given article. The blanks are always at the end of the question, and can be filled with more than one word or phrase.

Article: Halloween falls on October 31st, the last day of the Celtic calendar. Halloween was referred to as All Hallows Eve and dates back to over 2000 years ago. The American tradition of "trick-or-treating" probably dates back to the early All Souls' Day marches in England. During the festivities, poor citizens would beg for food and families would give them pastries called "soul cakes" in return for their promise to pray for the family's dead relatives. The act of giving out soul cakes was encouraged by the church as a way to replace the ancient practice of leaving food and wine for homeless ghosts. The practice, which was referred to as "going a-souling" was finally taken up by children who would visit the houses in their neighborhood and be given sweets, food, and money. The tradition of dressing in costume for Halloween has both European and Celtic roots. Hundreds of years ago, winter was an uncertain and frightening time. Food supplies were often not enough because people were afraid of the darkness and would stay at home without doing businesses. On Halloween, when it was believed that ghosts came back to the earthly world, people thought that they would meet with ghosts if they left their homes. To avoid being recognized by these ghosts, people would wear masks when they left their homes after dark so that the ghosts would mistake them for their fellows . On Halloween, to keep ghosts away from their houses, people would place bowls of food outside their homes to satisfy the ghosts and prevent them from trying to enter their houses.
Answer: praying for relatives
Output:
Halloween is a day _ .