What is the verb of sweet?

There is no verb directly related to "sweet". "Sweet" is an adjective, describing a quality.

Here are some verbs that relate to the concept of "sweet":

* Sweeten: To make something sweeter.

* Sugar: To add sugar to something.

* Flavor: To give something a sweet flavor.

* Savor: To enjoy the sweetness of something.

* Appreciate: To recognize and value the sweetness of something.

Let me know if you're looking for a verb for a specific context, and I can try to help you find the right one!