Đáp án:

`54,` I haven't been to a night club before.

`=>` It / This is the first time + S + have / has + V3 / PII

`=` S + have / has + not + V3 / PII + before

`55,` This is the first time they have heard such a thing. 

`=>` S + have / has + never + V3 / PII + (such + mạo từ + adj + N) + before

`=` This is the first time + S + have / has + V3 / PII + (such + mạo từ + adj + N)

`56,` This is the first time his authority has been challenged.

`=>` Bị động Hiện tại hoàn thành $(+)$ S + have / has + V3 / PII ( by O ).

`64,` This is the first time I have seen a dirter-looking dog.

`=>` S + have / has + never + V3 / PII + (such + mạo từ + adj + N) + before

`=` This is the first time + S + have / has + V3 / PII + (such + mạo từ + adj + N)

`75,` It is the first time I have met such a famous person.

`=>` S + have / has + not + V3 / PII + before

`=` It / This is the first time + S + have / has + V3 / PII

`76,` It is the first time she has seen that boy here.

`=>` S + have / has + not + V3 / PII + before

`=`  It / This is the first time + S + have / has + V3 / PII

`-` It / This + is + the + first / second / ... + time + S + have / has + VpII

`=>` Đây là lần thứ mấy đã làm gì

`-` S + have / has + never + VpII + ( such + a / an / ... + adj + N ) + before

`-` S + haven't / hasn't + VpII + ( such + a / an / ... + adj + N ) + before

`=>` Chưa từng làm gì trước đây

`*` I , You , We , They `+` have ( not )

`*` He , She , It `+` has ( not )

`54`.I haven't been to a night club before

`55`.This is the first time they have heard such a thing 

`56`.This is the first time his authority has been challenged 

`->` BĐ `-` HTHT : S + have / has + been + VpII ( by O )

`64`.This is the first time I have seen a dirter-looking dog

`75`.It is the first time I have met such a famous person 

`76`.It is the first time she has seen that boy here

`\text{# TF}`