It is scheduled for February 14 every year. According to legend, its origin is that St. Valentine, a young Christian missionary in ancient Rome, was arrested and imprisoned for venturing to spread Christianity, which touched the old jailer and his blind daughter and got their careful care. Before he was executed, Saint Valentine wrote a letter to the girl, expressing his deep affection for her. On the day when he was executed, the blind girl planted an apricot tree with red flowers in front of his grave to express her feelings. This day is 14 February. Now, on Valentine's Day, many young men also make postcards of courting St. Valentine into exquisite handicrafts and cut them into butterflies and flowers to show their sincerity and determination. Girls put laurel leaves on pillows at night, hoping to dream about their lovers. Usually on Valentine's Day, a red rose is given to express the feelings between lovers. A half-opened red rose is the best gift for a girl on Valentine's Day, and the girl takes a box of heart-shaped chocolates as a gift. It is said that phenylethylamine, one of the ingredients of chocolate, can cause hormonal changes in the human body, similar to the feeling in love.