I 'will not' AM UNABLE TO go 'to' FOR summer holidays 'in' TO England because my sister is going to get married. I have to take part in the wedding and help my parents in organizing THE ceremony. It will TAKE a lot of hours to prepare the ceremony.
I will have my birthday on 25TH July and I will invite you for my
biRthday. My 'birhday' (ortog) will be organized on THE 25th July at my home.
...I am looking 'foraward' (ortog) to hearing from you...(juz o tym pisalam, na nieformalny list to zdanie jest za formalne)