Cross out the by phrases when they are not necessary

01 Đề bài:

B. Read the sentences and cross out the by phrases when they are not necessary.

(Đọc các câu và gạch bỏ các cụm từ không cần thiết)

1. Energy is produced by the solar panels on top of our house.

2. In many countries, a lot of food is wasted by people.

3. Our notebooks are made from recycled paper by factory workers.

4. Eco-friendly cars are powered by electricity, not gasoline.

02 Bài giải: