J's (Biography of John Muir)-John Muir's own writings to bring readers a life story of this remarkable man who did so much to raise American's awareness of environmental issues. As America's first environmentalist, John Muir lived his life forever daring to undertake new adventures. He spent most of his days outdoors and had deep love for the wild lands. In the book, we meet John Muir as a youth fearlessly climbing the roof of his house. He captures birds only to let them go when he realizes the cruelty involved. He becomes an inventor and sells his inventions in order to attend the university. As a young man, he began walking over tens of thousands of miles during his lifetime, through the south to Florida, the west to California and north to Alaska, where readers are taken a long and particularly hair-raising adventure on a large mass of floating ice. Muir's learning in observation throughout his life led him to devote his last years to preserving the natural environment. His writing and speaking raised the awareness of the importance of conservation and helped bring about our national park system. Readers will feel they know John Muir after reading his story and may catch his passion for preserving the riches of our land. The other's portrayal of Muir's life is a testimony to what it means to be lifelong learners and to use that learning to inform and bring about change.
（约翰·缪尔的自传）约翰·缪尔为提升美国人的环保意识做出了很大贡献，他的自传使读者了解了这位杰出人物的生平 。作为美国首位环保主义者，约翰·缪尔的一生一直勇于尝试新的冒险 。他一生中大部分时间都在户外度过，他深爱着荒原地带 。在这本自传中，我们能看到约翰·缪尔小时候勇敢地爬上他家的房顶 。当他意识到捕鸟是种残忍行为时，他捕到鸟后就会把鸟放生 。后来他成为了一名发明家，为了上大学他开始出售他的发明 。他一生中走了数万英里的路，他从年轻的时候开始行走，南至佛罗里达州，西至加利福尼亚州，北到阿拉斯加州，读者会看到他在大块浮冰上的惊险历险 。缪尔这一生所记录的心得是在他晚年呼吁保护自然的主要动力 。他的文章和讲话提高了民众对保护重要性的认识，并促成了国家公园体系的建立 。读者在看完他的故事以后，会了解约翰·缪尔，激发出保护这片富饶土地的热情 。关于他人对缪尔传奇一生的写照证明了人要活到老学到老，同时要传达知识、带来变化 。
Questions 19 to 21 are based on the passage you have just heard.
Questions 19. What kind of book is the speaker introducing?
Questions 20. What do we learn about John Muir when he was young?
Questions 21. What did John Muir intend to do through writing and speaking?