24. There's the lady whose dog was killed.

25. He's the person whose car was stolen.

26. They're the people whose shop burned down last week.

27. I I'm the person  whose flat you stayed.

28. This is a story of a group boys whose plane crashed on an uninhabited island.

29. This is Mrs. Jones, whose son won the championship last year.

30. I know the woman whose son you bought the car from.

31. The roads were crowded with refugees, many of which were wounded.

32. The lorry crashed into a bus-load of schoolchildren, six of whom were slightly injured.

33. In prison they fed us on dry bread, most of which was mouldy.

34. I saw several houses, most of which were quite unsuitable.

35. He introduced me to his students, most of whom were from abroad.

36. He expected me to pay 2$ for 12 eggs, four of which were broken.

37. They gave me four very bad tyres, one of which burst before I had driven four miles.

38. The car crashed into a queue of people, four of whom were killed.

39. We need a room in which we can study.

40. He invited her to eat out on a day, on which it rained heavily.

41. The day on which she arrived was sunny.

24/There's the lady. Her dog was killed.

=>there's the lady whose dog was killed.

25/ He's the person. His car was stolen.

=>He is the person whose car was stolen

26/ They're the people. Their shop burned down last week.

=>They're the people whose shop burned down last week.

27/ I'm the person. You stayed in my flat.

=>I'm the person whose stayed in my flat

28/ This is a story of a group boys. Their plane crashed on an uninhabited island.

=>This is a story a group of boys whose plane crashed on a uninhabited island.

29/ This is Mrs. Jones. Her son won the championship last year.

=>This is Mrs. Jones whose  son won the championship last year.

30/ I know the woman. You bought the car from her son.

=>I know the woman who bought the car from her son

31/ The roads were crowded with refugees. Many of them were wounded.

=>The roads were crowded with refugees, many of whom were wounded

32/ The lorry crashed into a bus-load of schoolchildren. Six of them were slightly injured.

=>The lorry crashed into a bus-load of schoolchildren, Six of whom were slightly injured

33. In prison they fed us on dry bread. Most of it was mouldy.

=>In prison they fed us on dry bread, most of which was mouldy.

34. I saw several houses. Most of them were quite unsuitable.

=>I saw several houses, most of which were quite unsuitable.

35. He introduced me to his students. Most of them were from abroad.

=>He introduced me to his students, most of whom were from abroad

36. He expected me to pay 2$ for 12 eggs. Four of the eggs were broken.

=>He expected me to pay 2$ for 12 eggs ,four of which were broken

37. They gave me four very bad tyres. One of them burst before I had driven four miles.

=>They gave me four very bad tyres. one of which burst before I had driven four miles.

38/ The car crashed into a queue of people. Four of them were killed.

=>The car crashed into a queue of people, Four of whom were killed

39/ We need a room. We can study in that room. 

=>We need a roomin which we can study 

40/ He invited her to eat out on a day. It rained heavily on that day

=>He invited her to eat out on a day when it rained heavily 

41/ The day was sunny. She arrived on that day.

=>The day  on which she arrived was sunny

42/ September 2nd 1945 was the date. President Ho Chi Minh declared the Independence of Vietnam on that date.

=>September 2nd 1945 was the date on which president Ho Chi Minh declared the Independence of Vietnam 

43/I am going to visit the town. I was born and grew up in the town.

=>I am going to visit the town in which I was born and grew up

44/ Hanoi is the city. I was born in it.

=>Hanoi is the city in which I was born