Question

求老师解答：短文改错. 短文改错. In the past,man d

Answer 1

1.don't→didn't 2.were→weren't; were后加not 3.nature→natural　 4.A→The 5.In→At

6.pollute→polluting 7.bottle→bottles 8. and-or 9.kind→kinds　 10.them → which; 或some前加and