Only add Checkbox values when they have been selected

Hi,

I only want to add Checkbox values to the email sent when they have been selected. If they remain unchecked, that I do not want to include anything in the email for the specific checkbox.

At the moment, every checkbox is added to the email irrelevant of whether they are selected or not. Just that the ones that are selected show the appropriate value as well.

How can I do this.

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