Complete IELTS book 2 Unit 5-6 WB

a layer of soil that is permanently frozen, in very cold regions of the world

without carbon

to gradually get more and more of something over a period of time

thaw

connected with growing crops such as wheat

describing or relating to the climate zone south of the Arctic

a person or thing that you use or have instead of the one you normally use or have

fuel made from plant or animal sources and used in engines

to leave somebody, especially somebody you are responsible for, with no intention of returning

o mention something as a reason or an example, or in order to support what you are saying

tthe need to limit the amount of greenhouse gases being __________ into the atmosphere