请根据文章内容判断下面句子正误。 Black Friday Black Friday is the Friday following Thanksgiving in the US. On this day, the Christmas shopping season begins and large stores all over the US have sales. Recently, Black Friday has been the busiest shopping day of the year in the US. The name “Black Friday” originated in Philadelphia where it was used to describe the heavy traffic in the city after Thanksgiving. Later, another explanation of the name was made.When a company loses money, we say it is “in the red” and when it makes money, it is “in the black”. So “Black Friday” has come to symbolize the day when companies can start to make a big profit. Black Friday has caused some problems. In 2008, a crowd of 2,000 shoppers were waiting outside a local Wal-Mart in New York. When the store opened, everyone rushed in and one person was killed in the crush. Due to incidents like this one, many people now do their Black Friday shopping online. It is common for people to wait until Monday to do this because they can buy things online that do not sell over the weekend. This has led to a new name for the Monday after Thanksgiving---Cyber Monday. 句子: Black Friday is the Friday before Christmas.