=>
III/
1. The environment is affected in many ways by pollution.
2. We find it impossible to predict when the earthquake will happen. / We can't predict when the earthquake will happen.
3. Chemicals are being overused in their crops by some farmers.
IV/
1. went/had finished
2. had met
3. went/had read
4. hadn't worn
5. had started
6. had done/went
7. had lived/moved
8. told/had learned
9. had worked/retired
10. got/had already started
11. came/had changed
12. had grown
13. came/had waited
14. listened/had done
15. went/had gone
