Commands to move easily between the lines of PowerShell console 2.0 and 3.0

Hi

I would like to knowthe commands to move easily between the linesof PowerShell console 2.0 and 3.0?
If I'm writing a command on several lines and I want to correct a mistake that I made in a previous line, how do I do this?

What is the command to go back to the prompt without running the instruction just written?

Thanks

Bye

Have you got a copy of the powershell manual:

Windows PowerShell Shortcut Keys