When you ask a yes/no question that requires a follow-up question depending on the vendor's response, you can do that easily in the system. 

Step 1: Drag and drop the yes/no question type into the questionnaire
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Step 2: Select "add more if selected" to either the yes or no response. You can add more for both but you need to start with one.
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Step 3: Drag and drop your follow-up question type in the space just underneath your selected response. 

Step 4: Include text for your original question and your follow-up question. Lastly, hit the "save" button and you're all set!
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