（目录） 1
Unit Six 1
Part One Discourse Features 1
Calculation and Measurement 1
Sample A The Interior of the Earth 6
Sample B The Growth of Population 11
Sample C Global Effects of Pollution on Climate 18
Part Two Readings on Scientific Topics 26
The Science of the Parranormal 26
Passage A 26
Passage B 34
Passage C 39
Passage D 43
Unit Seven 49
Part One Discourse Features 49
Argumentation 49
Sample A Embattled Genes 52
Sample B The Need for Intermediate Technology(Ⅰ) 59
Sample C The Need for Intermediate Technology(Ⅱ) 65
Part Two Readings on scientific Topics 71
Space Science 71
Passage A 71
Passage B 77
Passage C 83
Passage D 86
Passage E 90
Unit Eight 98
Part One Discourse Features 98
Science Abstracts 98
Part Two Readinngs on Scientific Topics 113
Genetic Engineering and Biochemistry 113
Passage A 113
Passage B 119
Passage C 129
Passage D 134
Foreign Trade and Business Letter 142
Unit Nine 142
Part One Discourse Features 142
Sample A 146
Sample B 147
Sample C 149
Sample D 150
Sample E 151
Part Two Readings on Scientific T opics 154
Commerce 154
Passage A 154
Passage B 161
Glossary 169