`1.`It is known as Tet Nguyen Dan, or Tet.

`=>`Dẫn chứng : It is especially known as Tet Nguyen Dan, or Tet. ( Câu 2 của bài )

`2.`Yes , it is.

`=>`Dẫn chứng : Vietnam’s New Year is celebrated according to the Lunar calendar. ( Câu văn đầu tiên của bài )

`3.`It begins between January twenty-first and February nineteen.

`=>`Dẫn chứng : It begins between January twenty-first and February nineteen. 

`4.`They tidy their houses, cook special food, clean and make offerings on the family altars.

`=>`Dẫn chứng : They tidy their houses, cook special food, clean and make offerings on the family altars.

`5.`Yes, they do.

`=>`Dẫn chứng : On the New Year’s Eve, people sit up to midnight to see New Year in, then they put on new clothes and give one another the greetings of the season.

`6.`No, it doesn't.

`=>`Dẫn chứng : Tet lasts ten days.

`7.`Because Vietnamese people believe that how people act during those days will influence the whole year.

`=>`Dẫn chứng : Vietnamese people believe that how people act during those days will influence the whole year.