Several different stories are told about the origin of Saint Valentine's day. One legend dates as far back as the days of Roman Empire. According to the story , Claudius , the Emperor of Rome, wanted to increase the size of the army. He knew that it would be easier to get young men who were not married to join the army; therefore, he made a rule that no young men could marry until he had served in the army for a number of years.  A priest named Valentine broke the rule and secretly married a great number of young people. Finally, Claudius found out about Valentine and put the priest in prison, where he remained until his death on February 14.  After his death, Valentine was made a saint and the day of his death was named Saint Valentine's day--- which is time for people to send one another their greetings of many kinds.  February 14, Valentine's Day, is sweetheart's day, on which people in love with each other express their tender emotions.  People sometimes put their love message in a heartshaped box of chocolate or a bunch of flowers tied with red ribbons. Words of letters may be written on the flower-covered card, or something else. Whatever the form may be , the message is almost the same: "will you be my Valentine?" The passage mainly tells us about   _
how Valentine died. the Emperor of Rome how Valentine's Day is celebrated the origin of Valentine's Day