We've just released the ability to duplicate an existing online form. It means if you ever want to create new forms with similar questions you don't need create the form from scratch.
To copy a form go to your forms list from the admin menu.
Click the copy button
Now make any changes to the form like the name or description and click save.
You will then have a new form in the list, click the build button to make the changes required to the copied form.