Rewrite 1. I think you should use energy efficient light bulbs. -If I....... 2. He produced a great idea for our environment project. -He came....... 3. Because she was adsent from the meeting, she didn't know the resolution. -Because of........ 4. I won't take part in the volunteer program because I don't have enough free time. -If I...... 5. We need to reduce our plastic waste, otherwise we'll threaten our own existence. -If we.... 6. Due to the hurricane last night, I was without electric power. -Since there....... 7. People dumped toxic waste Products into the rivers or landfill sites. -Toxic waste products....... 8. Air pollution deaths will double by 2050 if the nations don't act. Unless........ 9. As the world's temperature rise, the Arctic keeps losing its ice. Due...... 10. I live by the sea, so I'm really worried about global warming. If I...... 11. I won't help you if you don't try your best. Unless..... 12. We'll come to the meeting if we aren't busy. Unless......