Introduction 4
Table of Contents 5
How to Study 6
Unit 1·Public Transportation 9
Unit 2·Bank＆Post Office 25
Unit 3·Electronic Devices 41
Unit 4·News 57
Appendix 74
Words＆Expressions 74
Power Up！ Listening＿ Dictation＆script 81
Level 4 Book 3 Syllabus 84