Lesson Thirteen 1
Text:Serve the Pec？Supplementary Reac？DiaryLesson Fourteen 19
Text:Matter in Three Physical States？Supplementary Reading:Elements Compoun？ MixturesGrammar:The Attributive Clause(Part Ⅱ)Lesson Fifteen 37
Text:Pure Water and Natural Water Supplementary Reading:WaterLesson Sisteen 53
Text:China's First 12,000-ton Hydraulic PressSupplementary Reading:The Bnilding of the 12,000-ton Hydraulic PressGrammar:The Noun Clauses Introduced by "What"Lesson Seventeen 73
Text:Mechanical DrawingsSupplementary Reading:How to Reprexent Machinc Parts in a DrawingGrammar:The Emphatic ItLesson Eighteen 92
Text:Words in ScienceSupplementary Reading:Conversion in English WordsGrammar:The Subjunctive MoodLesson Nineteen 111
Text:The Structure of the AtomsSupplementary Reading:Atomic StructureLesson Twenty 128
Text:Laboratory WorkSupplementary Reading:HeatGrammar:The Adverbial Clauses introduced by"that"Lesson Twenty-One 150
Text:The Concept of WorkSupplementary Reading:DynamicsLesson Twenty-two 162
Text:What is the Source of Correct Ideas?Supplementary Reading:Freedom and NecessityGrammar:A Brief Summary of the Usage of"As"Quotations from Chairman Mao Tse-tung 203