1. People say that they bought this shop last year.
It is said that they bought this shop last year.
They are said to have bought this shop last year.
2. "How much do you think it will cost?" he said to me,
He asked me how much I thought it would cost.
3. Mr.Brown's team has lost the game. He looks very sad. (Use relative clause)

Mr.Brown whose team has lost the game looks very sad. 
4. Do you know the man who sat next to me at Nam's birthday party last night?
You know man who sat next to me at Nam's birthday party last night, don't you?
5. We were late for school because of the heavy rain.
Because it rained, we were late for school.
6. "I'm working in a restaurant, and don't care much for it."she said
She said she was working in a restaurant, and didn't care much for it.

1. People say that they bought this shop last year

-> They are said to have bought this shop last year.

Mình chỉ bt làm c1 thôi/

2. “How much do you think it will cost ?” he said to me

-> He asked me how much I thought it would cost.

3. Mr.Brown’s team has lost the game. He looks very sad

-> Mr. Brown whose team has lost the game looks very sad.

4. Do you know the man who sat next to me at Nam’s birthday party last night?

-> You know the man who sat next to me at Nam’s birthday party last night, don’t you?

5. We were late for school beacause of the heavy rain

-> Because it rained heavily, we were late for school.

6. “I’m working in a restaurant, and don’t care much for it.” she said

-> she said that she was working in a restaurant and didn’t care much for it.