Is there sun hat?
No, there isn't.
Is there any shell?
Yes, there is.
There are a sandcastle.
False => There is a sandcastle.
Are there shells?
No, there aren't.
Are there shells?
No, there aren't.
Are there sandcastles?
Yes, there are.
There isn't people in the restaurant.
False => There aren't people in the restaurant.
There isn't a boat on the ocean.
True
Is there a beach ball?
Yes, there is.
There isn't a hat.
true
Is there boat on the ocean?
Yes, there is.