Here's why:
* Infinitives are the base form of a verb, usually preceded by "to" (e.g., "to run", "to eat"). They don't function as verbs on their own in a sentence.
* Finite verbs are verbs that are conjugated to show tense, person, and number. They are the verbs that actually perform the action in a sentence.
Example:
* Infinitive: To run
* Finite verb: "I run every morning." (present tense, first person singular)
When you change an infinitive into a finite verb form, you are giving it the ability to be the main verb in a sentence after a subject.