Choose the correct prepositions to complete the sentences. 1 Scientists have put global warming on / down to industrial pollution.
2 International governments need to set out / on new rules to help protect many animal species.
3 We go over /through a lot of food every week, but we don't throw much off / away.
4.Governments need to speed on /up research into environmental problems.
5 Big companies must pay over / up if they break environmental laws.