Find a mistake and correct it. 27. There are two bookshelf in my sister’s bedroom 28. I can see that there is a vase behind of the light 29. How many classes is there in your school? 30. Nam studys the past and present events in Vietnam and around the world 31. There are a banana and five oranges on the table 32. Hoa’s friend have a lot of English books 33. Ba always do his homework in the evening 34. My students is learning English lesson in their classroom 35. Is there four chairs in Lan’s room 36.Her sister walks usually to school every morning 37. Do your sister often do a lot of exercises after school ?