Here's how we know:
* Transitive verbs require a direct object. This means the verb describes an action that is done *to* something.
* "Eat" often describes an action done to food.
Examples:
* "I eat an apple every day." (The apple is the direct object of the verb "eat")
* "The dog eats its kibble." (The kibble is the direct object of the verb "eat")
Let me know if you'd like more examples or have any other questions!