12. If we don't use renewable energy, we will have nothing for the future generation.
13. If we don't reduce the use of non-renewable energy, the climate will change.
14. If you lock all the doors, no one can't break into your house.
15. If we don't continue hunting polar bears, they will not become extinct in near future.
12 If we don't use renewable energy, we will have nothing for the future generation
13 If we don't reduce the use of non-renewable energy, the climate will change
14 If you lock all the doors, no one can break into your house
15 If we don't continue hunting polar bears, they will not become extinct in near future
