1　Giving definitions

2　Classification

3　Description 1:occupations

4　Description 2:size ＆ prospects of a company

5　Revision

6　Description 3:properties ＆ abilities

7　Description 4:structure ＆ function

8　Description 5:conditions ＆ problems

9 Description 6:process ＆ method

10　Revision

11　Introducing an idea

12　Developing an idea 1

13　Developing an idea 2

14　Concluding an idea

15　Revision