Dear Tom,
Thanks for your letter - it was great to hear from you. I'm sorry I haven't written for ages, but I've been really busy preparing for my exams. It's really good news that you've passed your driving test. Congratulations!
Thank you so much for your invitation to stay with you for a week in July - I'd love to come.I know that you have a wonderful beach near your house, and I'd really enjoy spending some time there. I expect that the weather will be hot, so I hope we can go swimming.
You said that I don't need to bring much with me. What sort of clothes should I pack? Casual or formal? Would you like me to bring anything for you? I would like to bring something special for you and your family.
I'd better stop now and get on with my studying. I hope you're enjoying driving your car, and I'm looking forward to seeing you in July!
Thanks again for the invitation.
All the best,
Gedas