10. The last time I saw Linda, she looked very relaxed. She explained she'd been on holiday the ____ week.

A. ago                         B. following                C. next                        D. previous

11. Fossil fuels which are non-renewable pollute the air and cause air ____.

A. pollution                 B. solution                  C. contaminate            D. consumption

12. Recycling provides a method of reducing the amount of waste materials that gets to the landfills - thus ____ it less probable for environmental pollution to take place.

A. making                   B. doing                      C. causing                   D. trying

13. If wastes are thrown ____, they can cause pollution in water, land and air.

A. inappropriately      B. disappointingly      C. eco-friendly           D. favourably

14. Trees not only bring nature to urban areas, but they also help clean the air by absorbing pollutants, ____ oxygen, ____ water, and grow food.

A. to provide - to save            B. to provide - save        C. providing - saving            D. provide - save

15. Air pollution is such a serious ____ that it has been a direct factor in the ____ of millions of people each year.