`Đáp` `án:`

50. She has not visited her parents for 5 years.

51. I haven't written to my uncle since July.

52. We have been close friends for a long time.

53. John has collected stamps since 2000.

54. He has never gone abroad before.

55. He has drunk for a month.

56. They have had that car for five years.

57. We have eaten since it started to rain.

58. I haven't had my hair cut since I left her. 

59. She hasn't spoken to him for 5 months.

60. We haven't met for a long time.

61. How long have you had it?

62. I have never had such a delicious meal before.

63. The last time I saw him was 8 days ago.

64. It's been two days since they last took a bath.

65. She lived in London in 1985.

66. My father started working for that company 4 years ago.

67. They started seeing that film 30 minutes ago.

68. My grandfather gave up smoking last year. 

69. He wrote two letters 15 minutes ago.

70. How long is it since he left for England?

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Các công thức đổi HTHT - QKĐ

Loại 1: 

S + has/have + not + V3/ed + for/since + time 

--> S + last + V2/ed 

--> The last time + S+ V2/ed + was + time + ago

--> It is / has been + time + since + S+ (last) + V2/ed 

Loại 2: 

How long + has/have + S+ V3/ed?

--> When + did + S + V1?

--> How long is it + since + S+ V2/ed ?

--> How long ago + did + S + start / begin + to V / Ving? 

Loại 3:

S + has/have + V3/ed + for/since + time 

--> S + started / began + to V / Ving 

--> It is / has been + time + since + S+ V2/ed 

Loại 4: 

S + has/have + not/never + V3/ed + ... before

--> This/It is the first time + S+ has/have+ V3/ed

Loại 5:

When + did + S + last + V1?

--> When + was the last time + S + V2/ed?