Change the active into the passive. 4. They grow rice in the north. 5. We don't raise cows on our farm. 1. People used oil-lamps years ago.

Để chuyển câu cầu sang câu bị động, chúng ta cần thay đổi thì và thêm từ khóa "by" để chỉ người thực hiện hành động.

4. Rice is grown in the north by them.
5. Cows are not raised on our farm by us.
1. Oil-lamps were used years ago by people.

Oil-lamps were used years ago.

Cows are not raised on our farm.

Rice is grown in the north.