Hi! (dobrze by było wskazać tu osobę, do której piszesz czyli np. Dear Michael,)
I'm XYZ. I'm 18 years old. I'm a student and I live in ABC. I received your letter in September and I replied then. Did you receive my response?
I remember my holidays with great fondness. Holiday is the best (the most perfect - najbardziej idealne - to wg mnie niezbyt pasuje) time of the year. Not going to school for two months itself makes them such great. But there is still a few things that can make holiday even greater. One of the most important things about summer is the weather. It should be hot, the sun should shine all the time, so that the people could sunbathe, swim in the see or lake and take long walks in the evening... Rainy and cold weather can ruin this beautiful time! Last holiday I spent in Mazury (nie możesz pisać w czasie present perfect o czynności dokonanej). Poland's lake district is in Mazury, in the north-east of the country. It's a beautiful, clean land of lakes and forests. It was fantastic! I went there with my family. The weather was hot and sticky. I think that the smoked salmon is really very tasty! Moreover, everyday I ate a lot of ice-creams and cakes. I think I (wydaje mi się, że tu będzie past simple ale pewna nie jestem) put on weight :).
What did you do in your holiday?
Please, write back to me soon.
Best wishes,
XYZ