Hello,

You can use Alternative form layouts, which are meant for just such cases. All you need to do is define your alternative forms in:

CMS Desk -> Tools -> Forms -> {edit} -> Alternative forms

And afterwards insert the On-line form web part on your page and select the alternative form in web part's Alternative form name property.

You can find more information in our documentation on Alternative forms.

Please let me know if you need further assistance.

Regards,
Josef Dvorak