Unit One 1
Big Bucks the Easy Way 1
Unit Two 23
Deer and the Energy Cycle 23
Revision Exercises 1 43
Unit Three 66
Why Do We Believe That the Earth Is Round? 66
Jim Thorpe 84
Unit Four 84
Revision Exercises 2 110
Unit Five 135
To Lie or Not to Lie--The Doctor s Dilemma 135
Unit Six 157
How to Mark a Book 157
Revision Exercises 3 173
Unit Seven 198
The Luncheon 198
The New Cave 217
Unit Eight 217
Revision Exercises 4 229
Unit Nine 254
Journey West 254
Unit Ten 275
Why People Work 275
Revision Exercises 5 298
Test Paper 1 322
Test Paper 2 343
Keys to Revision Exercises 1 363
Appendix I 363
Keys to Revision Exercises 2 365
Keys to Revision Exercises 3 368
Keys to Revision Exercises 4 370
Keys to Revision Exercises 5 372
Appendix Ⅱ 376
Keys to Test Paper 1 376
Keys to Test Paper 2 378