The appropriate verb is "are" and the sentence will be "Three miles are too far to walk.
What is a verb?
It should be noted that a verb simply means an action word. It's used to show that an action has taken place.
In this case, the appropriate verb is "are" and the sentence will be "Three miles are too far to walk.
Learn more about verbs on:
https://brainly.com/question/1718605
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