10.更少使用地铁use the subway

9.更多/更少的污染more/less pollution

8.更多/更少的树more/few trees

7.一张纸a piece of paper

6.一百年之后in 100 years

5.活到200 岁live to be 200 years old

4.免费的be free

3.将来in the future

2.在家通过电脑学习study at home on computers

1.在人们家中in people’s home