If you see a group of people dancing and singing on the street or in the railway station, you don't need to feel surprised．They are a flash mob （快闪族）, which is a group of people who come together suddenly in a public place, do something unusual for a brief period of time, and then quickly break up．They are usually organized with the help of the Internet or other digital communication network．At a predetermined time, they gather and perform some distractions（消遣） such as waving their hands and exchanging books, Then, they quickly break up before the police can arrive．Using mobile phones, the flash mob can change its location if the first one has been replaced for any reason．
Bill Lasik, senior editor of Harper’s Magazine, organized the first flash mob in Manhattan in May 2003 and the first successful flash mob came together on June 3, 2003 - after the first attempt was foiled at Macy's department store．Lasik claimed that the activity was designed to make fun of hipsters （起时髦的人）, and call attention to the cultural atmosphere．
Flash mob gatherings can sometimes shock people．Such an activity might seem amusing and untrue, but it also might frighten people who are not aware of what is taking place．Undoubtedly, flash mobs can serve as good political tools in any direction．They also have great economic potential, such as using flash mobs to advertise a product．
The flash mob is now becoming more and more popular．People use it to do many things．For example, in 2009, Michael Jackson's fans took part in a flash mob to remember him．Hundreds of his fans gathered singing and dancing Michael's famous song "Beat It" together．Flash mobs give people from all walks of life an opportunity to come together to create a memory．
小题1:The undefined word "foiled" in Paragraph 2 can be replaced by _ 。
A．forgotten
B．prevented
C．announced
D．confirmed小题2:What can you learn about the flash mob from the passage?
A．The flash mob usually breaks up quickly for lacking enough time．
B．Once the place for the activity is determined, it can't be changed．
C．The flash mob can be made use offing many fields just for fun．
D．It gives people the chance to come together to do something unusual．小题3:The main purpose of the passage is -
A．to entertain
B．to encourage
C．to inform
D．to persuade小题4:The writer's attitude towards the flash mob is
A．negative
B．favorable
C．objective
D．doubtful
小题1:B
小题2:D
小题3:C
小题4:B
题目分析: 如果你在街上或者火车站看到一群人唱歌跳舞，你不必惊讶，这是快闪族在活动。快闪族是一群在公共场所突然聚集在一起的人群，做一些不同寻常的事情，然后快速解散。在本文中作者对快闪族进行了一些介绍。
小题1:B词义猜测题。根据第二段the first successful flash mob came together on June 3, 2003 - after the first attempt was foiled at Macy's department store．中破折号的作用可知前后句是解释说明作用，由此判断他们在成功集会之前曾经被阻止过，故B选项正确。
小题2:D细节理解题。从文章首段They are a flash mob （快闪族）, which is a group of people who come together suddenly in a public place, do something unusual for a brief period of time, and then quickly break up．可知D选项正确。
小题3:C推理判断题。本文主要介绍了快闪族的形成、活动方式以及特点等，属于说明文范畴，故答案选C。
小题4:B推理判断题。根据文章第三段作者的用词shock、frighten以及Undoubtedly, flash mobs can serve as good political tools in any direction可知作者对此持反对态度，选B。