Form skip through- conditional

I may have the subject description slight wrong... ?

If I have a form that asks certain questions and based on the answer to one of those questions eg a dropdown field where it provides two options- truck or ship, then pending on the response the user is faced with certain additional questions through another form, which otherwise would not have been seen or been required to complete.

Can this be done?
If so is this tied in with the subform capability?
Is there an example somewhere of this working and how it is done?

Thanks in advance.