Complete the following passage with the words or phrases in the box. Each can only be used once（将下列单词或词组填入空格。每空格限填一词，每词只能填一次。注意有一个多余选项）：

    Thanksgiving Day is a big holiday in America. It falls on the fourth ____ in November. The day after Thanksgiving Day is Black Friday. It has become the ____ shopping day of the year in America. Why is it called Black Friday? How did it become ____ a big shopping day?

    In fact, nobody is ____ where the name comes from. Some people say the term Black Friday from Philadelphia in the 1960s. At that time, the police used the term to describe the traffic jam that happened on the day after Thanksgiving Day.