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Lesson 1 Finding fossil man_知识拓展（成人版）.mp4
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Lesson 10 Silicon valley_知识拓展（成人版）.mp4
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Lesson 11 How to grow old_知识拓展（成人版）.mp4
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Lesson 12 Banks and their customers_知识拓展（成人版）.mp4
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Lesson 13 The search for oil_知识拓展（成人版）.mp4
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Lesson 14 The Butterfly Effect_知识拓展（成人版）.mp4
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Lesson 15 Secrecy in industry_知识拓展（成人版）.mp4
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Lesson 16 The modern city_知识拓展（成人版）.mp4
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Lesson 17 A man-made disease_知识拓展（成人版）.mp4
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Lesson 18 Porpoises_知识拓展（成人版）.mp4
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Lesson 19 The stuff of dreams_知识拓展（成人版）.mp4
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Lesson 2 Spare that spider_知识拓展（成人版）.mp4
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Lesson 20 Snake poison_知识拓展（成人版）.mp4
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Lesson 21 William S.Hart and the early‘Western’film_知识拓展（成人版）.mp4
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Lesson 22 Knowledge and progress_知识拓展（成人版）.mp4
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Lesson 23 Bird flight_知识拓展（成人版）.mp4
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Lesson 24 Beauty_知识拓展（成人版）.mp4
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Lesson 25 Non-auditory effects of noise_知识拓展（成人版）.mp4
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Lesson 26 The past life of the earth_知识拓展（成人版）.mp4
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Lesson 27 The ‘Vasa’ _知识拓展（成人版）.mp4
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Lesson 28 Patients and doctors_知识拓展（成人版）.mp4
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Lesson 29 The hovercraft_知识拓展（成人版）.mp4
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Lesson 3 Matterhorn man_知识拓展（成人版）.mp4
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Lesson 30 Exploring the sea-floor_知识拓展（成人版）.mp4
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Lesson 31 The sculptor speaks_知识拓展（成人版） .mp4
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Lesson 32 Galileo reborn_知识拓展（成人版）.mp4
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Lesson 33 Education_知识拓展（成人版）.mp4
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Lesson 34 Adolescence_知识拓展（成人版）.mp4
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Lesson 35 Space odyssey_知识拓展（成人版）.mp4
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Lesson 36 The cost of government_知识拓展（成人版）.mp4
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Lesson 37 The process of ageing_知识拓展（成人版）.mp4
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Lesson 38 Water and the traveller_知识拓展（成人版）.mp4
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Lesson 39 What every writer wants_知识拓展（成人版）.mp4
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Lesson 4 Seeing hands_知识拓展（成人版）.mp4
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Lesson 40 Waves_知识拓展（成人版）.mp4
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Lesson 41 Training elephants_知识拓展（成人版）.mp4
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Lesson 42 Recording an earthquake_知识拓展（成人版）.mp4
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Lesson 43 Are there strangers in space_知识拓展（成人版）.mp4
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Lesson 44 Patterns of culture_知识拓展（成人版）.mp4
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Lesson 45 Of men and galaxies _知识拓展（成人版）.mp4
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Lesson 46 Hobbies _知识拓展（成人版）.mp4
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Lesson 47 The great escape_知识拓展（成人版）.mp4
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Lesson 48 Planning a share portfolio_知识拓展（成人版）.mp4
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Lesson 5 Youth_知识拓展（成人版）.mp4
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Lesson 6 The sporting spirit_知识拓展（成人版）.mp4
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Lesson 7 Bats_知识拓展（成人版）.mp4
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Lesson 8 Trading standards_知识拓展（成人版）.mp4
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Lesson 9 Royal espionage_知识拓展（成人版）.mp4
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