Human: How can I remove a red wine stain from a shirt? Assistant: 
The best way to remove a red wine stain from a shirt is to first rinse the stain with cold water to dilute it as much as possible. Then, you can try applying a stain remover product, or mix equal parts white vinegar and water and apply it directly onto the stain. Alternatively, you can also make a paste with baking soda and water, applying it to the stain and allowing it to sit for about 15 minutes before washing it off.