Select box in a form

Hello, how can i add a placeholder in a selectbox? Required is true and i need a placeholder descirption for it. like:
option1: Which pet do you want most?
option2: cat
option3: dog

I added a placeholder option to the select field. Will be in the next Form plugin release: https://github.com/getgrav/grav-plugin-form/commit/5ed117d6c8e2f389ce624f77c5e95eabd69d8b3a

Thank you! Work perfect