Validation options for this 2 Column Form?

[discdemo]

Hi. This form is great in that it is responsive.

I have tested it out successfully, however ...

Is there any good way to specify a required field,
as well as display the field is required upon submission.
without it clearing the whole form?

I'm using a form handler with it. Some fields are set as required
in the handler, so .... if/when one is missed and the user submits,
it just clears the form.

I was hoping to make the form a little more
user-friendly. Thanks for any ideas!

http://www.dynamicdrive.com/style/csslibrary/item/responsive_2_column_form/

and I'm testing it, here:
http://vetsworkshop.org/vso-registration/

Thank you, once more.
jz