1. Farmer planted potatoes in this field last year.
=> Potatoes were planted in this field last year.
2.They held an English Speaking Contest at Nguyen Hue School last month. => An English Speaking Contest was held at Nguyen Hue School last month.
3. People discovered rubber in Brazil.
=> Rubber was discover in Brazil.
4. Clement Clarke Moore wrote the poem in 1823.
=> The poem was written by Clement Clarke Moore in 1823.
5. She gave me a present on my birthday.
=> I was reiceved a present on my birthday.
6. They didn’t look after the children properly.
=> The children weren't look after the properly.
Xin hay nhất ạ.