[Typo3] How can I get last <FORM> data in typoscript??

[Dennis Cheung]

Hi all,

I've make a page of formmail, and show thank you page after submitting.
And on the thank you page, I wanted to show some field value just submitted(
e.g. name).

Even more, I wanted to make a chain of form page like a wizard.
Keep last <form> data in hidden value, and process them at once.

How to do this by typoscript?
I've read TS document said is can use GET parameter in condition(but no
example, how??)

Do I must build my own plugin???

Thanks,
Dennis