51. Rosie has a sister?

Hey guys, lately I noticed despite the fact I am coming back to each of my chapter and correcting the mistakes even after time I always finds new one. I would really appreciate any help. I know I have some parasitic words which are removed by the app Grammarly later (thanks God for this app) but there are still nuances I don't really understand as a nonnative speaker. If you could point out my most usual grammatical mistakes, I would be very grateful for that.