You can set questions to become available depending on the answer(s) to previous question(s) by selecting the Conditional Element checkbox when editing a field.

For example, You could use radio buttons to ask if someone's stall uses gas, then if they answer yes, ask them for a mandatory gas safety certificate.

As it looks on the form builder:
Select the Conditional Element tick box
Select the Element to Check
Select Element Answer(s)

There may be times when you wish to reveal a new field based on several different answer selections on a previous question.

An example might be this - you are asking staff how they will be travelling to your event. The options are Car, Van, Bus, Train, Bicycle. You wish to ask them for the vehicle registration plate, but only if they select either Car or Van.

Select the Conditional Element tick box
Select the Element to Check
Select Element Answer(s) - do this by selecting Element Answers whilst pressing and holding down your Ctrl key (or equivalent)

This means that if applicants select either Car or Van, it will ask them for a registration plate.

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