list .. - sprawdzenie

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Hi Sarah!
How are you? I know that you are sick. How do you feel? I hope you feel better. I have had a pop concert at my school recently. Jonas Brother was a band who appeared . I know that you love this band. I have great news. They said that they are playing a concert at the restaurant "Island". There will be many great bands. This concert is being organized at seven o'clock on this Saturday. I know that you are interested in music, so I'd like to invite you on the concert. I can't go at seven o'clock because I am having a sister's birthday. How about meeting at eight o'clock at the restaurant?
Let me know of you can come.

How do you feel (dodaj tutaj 'now')?
There will be many great bands THERE.
I know that you are interested in music, so I'd like to invite you 'on' TO (you invite people TO the cinema, To the theatre,) the concert.
I can't go at seven o'clock because I am having 'a' MY sister's birthday PARTY.
Let me know 'of' IF you can come.