Read the passage and answer the questions.

Vietnam’s New Year is celebrated according to the Lunar calendar. It is officially known as Tet Nguyen Dan, or Tet. It occurs between January twenty-first and February nineteenth. Vietnamese people usually make preparations for the holiday several weeks before hand. They tidy their houses, cook special food and make offerings … On the New Year’s Eve, people sit up to midnight to see the New Year in, then they put on new clothes and give one another the greetings of the season. The first three days are the most important. Vietnamese people believe that how people act during those days will influence the whole year.

When does the Vietnam’s New Year occur?

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