３８、The following is a letter to the editor of an environmental magazine.
The decline in the numbers of amphibians worldwide clearly indicates the global pollution of water and air. Two studies of amphibians in Yosemite National Park in California confirm my conclusion. In 1915 there were seven species of amphibians in the park, and there were abundant numbers of each species. However, in 1992 there were only four species of amphibians observed in the park, and the numbers of each species were drastically reduced. The decline in Yosemite has been blamed on the introduction of trout into the parks waters, which began in 1920 . But the introduction of trout cannot be the real reason for the Yosemite decline because it does not explain the worldwide decline.
人教版高中英语选修七Unit 4《Sharing》word导学案
2013外研版必修一Module 4《A Social Survey -- My Neighbourhood》word学案（有答案）
人教版高中英语选修8 Unit 4《Pygmalion》word教案
2013外研版必修一Module 3《My First Ride on a Train》word教学案
2013外研版必修一Module1《My First Day at Senior High》word教案7
人教版高中英语选修8 Unit 3《Inventors and inventions》word导学案
人教版高中英语选修8 Unit 4《Pygmalion》word导学案
人教版高中英语选修8 Unit 1《A Land of Diversity》word导学案
人教版高中英语选修七Unit 5《Travelling abroad》word优秀教案（4份）
2013外研版必修一Module 5《A Lesson in a Lab》word学案（有答案）
2013外研版必修一Module1《My First Day at Senior High》word学案1
人教版高中英语选修8 Unit 1《A Land of Diversity》教案 练习 教学素材打包下载（16份）
2013外研版必修一Module 3《My First Ride on a Train》word学案（有答案）
2013外研版必修一Module 5《A Lesson in a Lab》word教案1
2013外研版必修一Module 2《my new teachers》word教案1
人教版高中英语选修8 Unit 2《Cloning》word教案
人教版高中英语选修七Unit 3《Under the sea》（Period 1）word教案
人教版高中英语选修8 Unit 2《Cloning》教案 练习 教学素材打包下载（14份）
2013外研版必修一Module1《My First Day at Senior High》word教案1
人教版高中英语选修8 Unit 2《Cloning》word导学案
人教版高中英语选修七Unit 4《Sharing》word优秀教案（3份）
2013外研版必修一Module 4《A Social Survey -- My Neighbourhood》word教案
人教版高中英语选修8 Unit 4《Pygmalion》教案 练习 教学素材打包下载（18份）
人教版高中英语选修8 Unit 5《Meeting your ancestors》word教案
2013外研版必修一Module 6《The Internet and Telecommunications》word教案
人教版高中英语选修8 Unit 5《Meeting your ancestors》word导学案
人教版高中英语选修8 Unit 3《Inventors and inventions》教案 练习 教学素材打包下载（16份）
人教版高中英语选修8 Unit 1《A land of diversity》word教案
2013外研版必修一Module 3《My First Ride on a Train》word教案1
2013外研版必修一Module1《My First Day at Senior High》word教案2