2.

1. Is Peter going to visit an island?

2. Are Sara and Peter going to go on holiday to Turkey?

3. Is Sara going to walk to the waterfall?

4. Are Sara and Peter both going to visit an island?

5. Is Peter going to walk to the waterfall?

3.

1.No, he isn't.

2. Yes, they are.

3. Yes, she is.

4. No, they aren't.

5. No, he isn't.