Want to work as a Linux Admin - How deep do my scripting skills have to be?

I read advanced scripting experience in bash/perl/php in a lot of job descriptions but I don't really know what they mean by advanced.

How far does my scripting experience has to be to be suiteable in a professional envrionment?

What would be some everyday scripting tasks (aka anything I could practice on my linux machines at home)?

^edit:grammar