Unit 1 Politeness
Unit 2 The power of smiling
Unit 3 What is happiness？
Unit 4 Family affection
Unit 5 Selfless dedication
Unit 6 Extraordinary people
Unit 7 Facing challenges
Unit 8 A victim or creator
Unit 9 Team power
Unit 10 Hi-tech around us
Unit 11 Psychological research
Unit 12 Imagination and fantasy
Unit 13 The outside world
Unit 14 Magical earth
Unit 15 Mysteries
Unit 16 Advice for you
Unit 17 Life tips
Unit 18 Longing for a clean world
Unit 19 Animal world
Unit 20 Advertisements
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