Here's why:
* Gerund: "Taking" is a gerund, which is a verb form ending in "-ing" that acts as a noun.
* Gerund Phrase: The phrase "Taking a warm bath" includes the gerund and its related words (a warm bath).
* Subject: The subject of a sentence is the person or thing performing the action. In this case, the action is "will relax" and the thing performing the action is "Taking a warm bath".
In summary: The sentence structure is: [Subject (gerund phrase)] + [Verb (will relax)] + [Object (your nerves)]