1.Did he make the model plane?
was the model plane made by him?
2.We grow rice in the south of China
rice is grown in the south of China
3.We must keep our classroom clean and tidy
the classroom must be kept clean and tidy by us
4.We can't ss the stars in the day time
the stars can't be seen in the day time by us.
5.They made him finish the work
He was made to finish the work