giải giúp em bài tập này với ạ, em cảm ơn

Here are the combined sentences using relative pronouns: 21. Smallpox, which once killed thousands of people every year, has disappeared. 22. I passed him a large glass of whisky, which he drank immediately. 23. The small man, who was Lisa's husband, was not recognized. 24. This is Mr. Jones, who writes poetry. 25. This is Felicity, whose sister you met last week. 26. He swam across the English Channel, which is hard to believe. 27. His wife, whose name was Angela, died last year. 28. Borges was a wonderful writer who never won the Nobel Prize. 29. A man from our village, whom I teach his children, was on TV last night. 30. Charlie Chaplin, whose films amused millions, died in 1977. 31. My parents, whom you met last month, send their best wishes. 32. The parcel, which they had opened carefully, contained a bomb. 33. The match, which they filmed this afternoon, will be shown on TV tonight. 34. His sisters, whom I saw last night, are identical twins. 35. The lady, whom you met at the party last night, is a famous writer. 36. The child enjoyed the chocolates, which her mother bought from France. 37. Dr. Oley, who is a popular dentist in the city, is our family's dentist. 38. They drank a lot of Coke, which is diet Coke. 39. The river, which flows through Ho Chi Minh City, is the Sai Gon River. 40. The girls, who rehearsed it yesterday, are performing the play.