1、题目关键词：examples and details, describe

 2、答题要领：

 (1)summarize the causes of the problems.

 (2)use examples and details to describe the causes and effects.

 3、听力材料要点：

 (1)Overfishing: fish population has dropped dramatically. Bottom trolling: catch huge quantities of fish. Destroy habitats and contribute to fish declines.

 (2)Pollution: kill marine life close to shores. Ships dump a large amount of petroleum products. Damage marine environments.

 (3)Climate change: new disease outbreaks in the sea. The loss of coral contributes to fish declines. Affect mammals that are fed on fish such as polar bears.

 4、模板

 (1)In the listening material, the professor discusses the causes and effects of problems that threaten the world's oceans.

 (2)First of all, ... For example, ...

 (3)Second, ...

 (4)Third, ...