Answer:
1. Next summer I <u>am going to </u>buy a new house.
2. I am quite tired; I <u>will </u>go to bed now.
3. I believe Laura <u>will </u>like her brand new car.
4. Look at those guys! They <u>are going to</u> rob the bank.
5. I promise, I <u>won't</u> do it again.
6. I think she <u>will </u>crash my dad's car.
7. I talked to John yesterday; we<u> are going to</u> visit you tomorrow.
8. I am sorry dad; I <u>won't </u>drink and drive again.
9. Watch out! That man <u>is going to</u> punch you.
10. It is really hot in here; I<u> will </u>open the window.
Explanation:
We use the future simple with -will-, to talk about predictions, where we do not know if an event or action is going to happen since there is no evidence to confirm it. Another use of will is to make promises, like in sentence number 5 ( I promise, I won't do it again.) and lastly to talk about decisions made at the moment like in sentence number 2 or 10 where the person decided at that moment what to do.
We use going to talk about arrange plans for the future, like in sentence number 1 or 7 where there is a plan to buy a house in the future or to visit someone on an exact date. The other use of going to is to talk about an action or event that is going to happen in the future and that there is evidence to confirm it. Like in sentence number 4, where the people saw the thieves, or in number 9, where the other person was moving the arm to punch him, this is evidence that an event is going to happen.