Question

1. The boat are in the beach/ harbour​

Answer 1

The boat are in the beach

Answer 2

The correct sentence is: "The boat is at the beach/harbor."

In this sentence, "boat" is singular, so the verb "is" should also be singular to match it. Additionally, you can use "at" instead of "in" to indicate the boat's location at the beach or harbor, depending on the context.