Dear Sara (imiona generalnie piszemy duza lit)
Warm greetings from łeba.
I've (I've to znaczy I have...czy teraz zdanie ma sens) staying at a
fabulous hotel next to the beach, so I have 'A' wonderful view of the
sea.
On Sunday 'I and Greg' (lepiej Greg and I) visited THE city and of course THE beach.
There iS clean and pleasantly (popraw to zdanie) We have also seen SANDdunes, we saw them yesterday. There was AN amazing view.
...been on a night 'voyouge' (voyage) ON the Baltic sea yet. We are going to start windsurfing, 'becouse' (NIE, BECAUSE) it is AN interesting sport.
łeba is perfect place 'on gut' (co to?) rest. Your holidayS 'are' (nie, nie tuttaj) here ARE the holidayS of your dreams. I'm returning to Wroclaw on Monday next week, so I'll talk you about my holiday 'than' (chyba THEN).
Zauwaz, uzycie 'the' 'an'.