精心整理精心整理Unit TwoTask 1FamiliarizingYourself with Classif ication1
Skim the following passage for the answers to the questions below
1) Man-made or anthropogenic causes, and natural causes
2) Pollution (burning fossil fuels, mining coal and oil, etc
), the production of CO( the increase ofpopulation, the demolition of trees, etc
) 3) COis a greenhouse gas that traps heat in the Earth’s atmosphere
4) Classif ication helps us to determine and understand the relationship of the parts of a subject which is studied by us
Classification is made on the basis of a clear definition
5) In order to make a clear and logic classification, one needs to follow a principle of classification and go on with a system consistently
For example, the categories of classification should be mutually exclusive