"Bring to a boil" is a verb phrase that describes the action of heating a liquid until it reaches boiling point. It implies a process of raising the temperature.
"The boil" is a noun phrase that refers to the state of boiling. It's the point at which a liquid is bubbling rapidly.
Here are some examples:
* Bring to a boil: "Bring the water to a boil, then add the pasta."
* The boil: "The water was at the boil when the phone rang."
You can also use the phrase "come to a boil," which is similar in meaning to "bring to a boil" but implies that the boiling occurs naturally rather than being caused by an external action.
Let me know if you have any more questions!