Chapter 9 The environment I.Teaching Objective: 1.Develop the student's awareness of the importance of environment on earth. 2.Help the students to know that biotic and abiotic environment are equal importance for survival and reproduction for an organism 3.Help the students to overcome difficulties both in psychology and linguistics in bilingual teaching. IL.Focal Points and Difficulties in the Chapter(教学重点和难点) 1.Focus Interspecific interactions:competition,predation,parasitism and mutualism, Intraspecific interactions:competition,cannibalism and altruism. Gause's competitive exclusion principle 2.Difficulties Biotic environment III.Methodology Powerpoint presentation will be the main method.Blackboard will be an assistance.Fifteen minutes'discussion will be arranged.Some beautiful diagrams have been prepared for visualization. V Presentation(课发讲解，学时分配为2学时左右) Step 1.Warm-up Activity List the main ecological problems both in China and all over the world Let the students have a understanding about importance of discipline of ecology in the chapter. Step 2.The students are required to finish reading the whole text before the class and try to understand the major points of the chapter.The students are supposed to underline the difficult words or structures and raise their questions concerning