There are many competing theories about the origins and nature of UFOs. For example, researchers Brad Steiger and Sherry Hansen Steiger have a list of seventeen theories at their website. In UFO: The Complete Sightings (1995) by Peter Brookesmith, there is a list of nine theories. Further, these theories are often categorized.In The Mammoth Encyclopedia of Extraterrestrial Encounters (2001) edited by Ronald D. Story, the subject is divided into “conventional (unintelligent)” and “unconventional (intelligent)” encounters.
1) Do you talk on the lessons? Don't talk on the lesson. 2) do you do tests? Don't do tests. 3) do you feed animals? Don't feed animals. 4) do you read English books? Don't read English books. 5) do you have great time in school? Don't have great time in school. 6) do you do experiment? Don't do experiments. 7) do you help friends? Don't help friends. 8)do you do our h/w? Don't do our h/w. 9)do you speak English? Don't speak English. 10)Do you play games? Don't play games 11) do you meet interesting people? Don't meet interesting people. 12)do you swim? Don't swim.
