1. They expect that more foreign tourists will return to Viet Nam after their first visit. 

⇒It is expected that more foreign tourists will return to Viet Nam after their first visit.

"Họ kỳ vọng rằng thêm nhiều du khách nước ngoài sẽ quay lại Việt Nam sau chuyến du lịch đầu tiên của họ."

2. People say that Vietnamese students lack knowledge of the wonders of Viet Nam. 

It is said that Vietnamese students lack knowledge of the wonders of Viet Nam.

"Người ta nói rằng học sinh Việt Nam thiếu kiến thức về các kỳ quan của Việt Nam."

3. They know that Hoi An was listed as a World Heritage Site in 1999. 

⇒It is known that Hoi An was listed as a World Heritage Site in 1999.

"Họ biết rằng Hội An đã được ghi nhận là một Di sản Thế giới vào năm 1999."

4. They have claimed that Ly Son has a pristine beauty that not many other islands can match. 

⇒It has been claimed that Ly Son has a pristine beauty that not many other islands can match.

"Họ nhận định rằng Lý Sơn sở hữu một vẻ đẹp nguyên sơ mà ít đảo khác có thể sánh bằng."

5. They thought that tourists should definitely visit the Imperial Citadel when arriving in Hue. 

⇒It was thought that tourists should definitely visit the Imperial Citadel when arriving in Hue.

"Họ đều đã nghĩ rằng khách du lịch nhất định nên đến thăm Cố Đô khi đến Huế."

CHÚC BẠN HỌC TỐT:)))))

1.

It is expected that more foreign tourists will return to vietnam after their fisrt visit.

Hoặc: More foreign tourists are expected to return to vietnam after their fisrt visit.

2.

It is said that Vietnamese students lack knowledge of the wonders of Vietnam.

Hoặc: Vietnamese students are said to lack knowledge of the wonders of Vietnam.

3.

It is known that Hoi An was listed as a world heritage site in 1999.

Hoặc: Hoi An is known to have been listed as a world heritage site in 1999.

4.

It has been claimed that Ly Son has a pristine beauty that not many other islands can match.

Hoặc: Ly Son has been claimed to have a pristine beauty that not many other islands can match.

5.

It was thought that tourists should definitely visit the imperial citadel when arriving in Hue.

Hoặc: Tourists were thought to definitely visit the imperial citadel when arriving in Hue.