Different cultures follow their own special customs when a child’s baby teeth fall out. In Korea, for example, they have the custom of throwing lost teeth up on the roof of a house. According to tradition, a magpie will come and take the tooth. Later, the magpie will return with a new tooth for the child. In other Asian countries, such as Japan and Vietnam, children follow a similar tradition of throwing their lost teeth onto the roofs of houses.
(Trích từ đề thi THPT Quốc gia 2017)
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