包邮21世纪实用英语基础教程综合练习

Unit 1 Heroes Part I Text Exercises Part II Exercises for PRETCO Unit 2 Water Resources Part I Text Exercises Part II Exercises for PRETCO Unit 3 Friends Part I Text Exercises Part II Exercises for PRETCO Test Yourself (for Units 1-3) Unit 4 Healthy Foods Part I Text Exercises Part II Exercises for PRETCO Unit 5 Shopping Days Part I Text Exercises Part II Exercises for PRETCO Unit 6 Lives in Nature Part I Text Exercises Part II Exercises for PRETCO Test Yourself (for Units 4-6) Key and Script