natto wrote:

Dear everyone,I'm a new member and very new for space science,so please
help me to learn about it!
I've read some forum about the figure of 8 but still do not understand
about it! May you please show me the picture or link of satellite's
motion?
Thanks a million.



Read up on it here, which has diagrams of it:
http://celestrak.com/columns/v04n07/
Sven Grahn has many interesting articles on satellites and satellite
tracking:
http://www.svengrahn.pp.se/
For doing satellite tracking, NASA has a page that shows where major
satellites are at in real time:
http://science.nasa.gov/Realtime/jtr.../JTrack3d.html
For everything space related, it's hard to beat Mark Wade's Encyclopedia
Astronautica website, which is huge:
http://www.astronautix.com/index.html
Hope this helps.

Pat