21世纪大学英语 综合练习 3 s版=21st century college english workbookPDF电子书下载

Unit 1 Career Competencies 1

Part Ⅰ Text Exercises 1

Part Ⅱ Exercises for CET-4 7

Unit 2 Sustainable Living 17

Part Ⅰ Text Exercises 17

Part Ⅱ Exercises for CET-4 22

Unit 3 Road to Success 33

Part Ⅰ Text Exercises 33

Part Ⅱ Exercises for CET-4 38

Unit 4 Space Technology 48

Part Ⅰ Text Exercises 48

Part Ⅱ Exercises for CET-4 53

Test yourself（for Units 1-4） 64

Unit 5 Travel 73

Part Ⅰ Text Exercises 73

Part Ⅱ Exercises for CET-4 78

Unit 6 Teaching 88

Part Ⅰ Text Exercises 88

Part Ⅱ Exercises for CET-4 93

Unit 7 Construction 104

Part Ⅰ Text Exercises 104

Part Ⅱ Exercises for CET-4 110

Unit 8 Code of Conduct 120

Part Ⅰ Text Exercises 120

Part Ⅱ Exercises for CET-4 126

Test yourself（for Units 5-8） 137

Test yourself（for CET-4） 146

Key and Script for Workbook（3） 157