50. If we knew her address, we could visit her.

If 1: If + QKĐ, S  + would / could + V1 

51. Because of the cold weather, they had to cancel their picnic.

because of + N / Np / Ving, clause: bởi vì 

52. This is the man whose son we are talking about.

N + whose + N 

53. It takes Nga two hours a day to practice English with her friends.

It takes + O + time + to V : mất bao nhiêu thời gian để làm gì 

54. My friend asked Ann if she went to school on Sunday.

S + asked + O + if/whether +S + V (lùi thì)

HTĐ ⇒ QKĐ

55. I wish I could come to your party.

S + wish(es) + S+ could + V1: ước ở hiện tại 

56. You took part in the English club last year, didn't you?

take part in: tham gia 

S + V2/ed, didn't  +S? câu hỏi đuôi 

57. I wish I had enough money to buy that electric bike.

S + wish(es) + S+ QKĐ: ước ở hiện tại 

58. Jack asked if Peter still worked at that factory.

S + asked + O + if/whether + S+ V (lùi thì)

HTĐ ⇒ QKĐ

59. Although Mary was tired, she tried to finish her homework.

Although + clause, clause: mặc dù 

60. Đúng

61. It is believed that the Covid-19 pandemic will end soon.

It + be + V3/ed + that + clause: bị động - không ngôi 

62. The teacher asked me why I wanted to take the course.

S + asked + O + WH + S+ V (lùi thì)

HTĐ ⇒ QKĐ

63. If Ann didn't have free time, she couldn't read many books.

If + QKĐ, S + would / could + v1: if 2 

64. Electricity will be brought to remote areas by the government.

S + will be + V3/ed: bị động - TLĐ

65. The singer who sings very well has just released a CD.

N (người) + who + V 

66. Linda asked me what I had done to avoid coronavirus.

S+ asked + O + WH + S+ V (lùi thì)

HTHT ⇒ QKHT 

67. Because she performed well, she received good comments.

because + clause, clause: bởi vì 

68. If you study hard, you will pass the exam.

if 1: If + HTĐ, TLĐ

69. A new car model will be introduced by Vinfast Automobile Company.

S + will be + V3/ed: bị động - TLĐ

70. Mary composes more creatively than her sister.

S + V+  more + ADV + than + O : ss hơn 

71. I wish I could see Susan off at the airport tonight. 

S + wish(es) + S+ could + V1: ước ở tương lai 

72. Đúng 

73. Mary told her brother that he had to wear face masks in public.

S + told + O + (that) + S+ V (lùi thì)

has/have to ⇒ had to

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