单词：half value layer
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CHAPTER ONE [00:44.25]READING [00:45.74]Page 2 and 3 [00:48.43]THE YOUNG GREEN CONSUMER GUIDE [00:51.51]Review by Tony Ma [00:54.62]This book says that our world is in danger [00:59.32]It is vital that we do something to save the earth [01:04.21]Firs
上海牛津初中英语九年级
I first heard about the ozone layer about twenty years ago. I was still in school. I thought it was interesting, but I didnt take it seriously. It was a bit like science fiction, I mean, how could there be a giant hole in the atmosphere? Over the yea
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语音讲解 1.half of 2.history 3.hide 词汇讲解 hide the truth 隐瞒真相 在英文中，conceal 表示隐藏，掩盖，隐瞒； hide也表示隐藏，那么这两个词的区别是什么呢？ hide 用途较广，可指偶然的隐藏、遮掩
自然拼读教材英语字母拼读法（学生用书）Book 3-2
There is a special day to recognize the importance of the ozone layer. In 1995, the United Nations General Assembly decided September 16th is the International Day for the Preservation of the Ozone Layer. This is the date on which countries signed th
英语课程学习计划和讲义
Task 2: A Work Qualification Test Script According to a report by Australian researchers, the hole in the ozone layer over Antarctica will probably start closing within five years. They say it may be completely closed within fifty years. The ozone la
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I first heard about the ozone layer about twenty years ago. I was still in school. I thought it was interesting, but I didnt take it seriously. It was a bit like science fiction, I mean, how could there be a giant hole in the atmosphere? Over the yea
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