Paragraph 2_______
A.Man should be cautious in chemical use.
B.It takes generations for mankind to adapt themselves to the chemicals.
C.Chemicals are human’s invention
D.Human’s power increases and has changed its character in the past quarter century.
E.The new change in the relationship between earth and its creature一human’s power playing a greater role in changing the world
F. Modern world gives no time for nature to adjust to human.