1. grasp the main idea( tolerance for solitude and energy made it possible for the writer s family to enjoy their pleasant but sometimes harsh country life.) 2. appreciate the various techniques employed by the writer comparison and contrast, topic sentences followed by detail sentences

Contents Teaching Objectives Background Information Text Organization Language Points

Contents Teaching Objectives Background Information Text Organization Language Points Discussion

Contents Teaching Objectives Background Information Text Organization Words and Expressions Grammatical Structures Discussion

Contents Teaching Objectives Background Information Text Organization Words and Expressions Grammatical Structures Questions

Part 1 Objectives Part 2 Background Part 3 Text Organization Part 4 Language Study Part 5 Translation

Part 1 ObjectivesPart Part 2 Background Part 3 Ddiscussion Part 4 Language Points Part Ccontent Questions Part 6 Translation

Text A Tony Trivisonno's American Dream Part 1 Obiectives Part Discussion Questions Part3 Background Part 4 Text Structure Part Lanquage Points

支持关系模型的数据库系统是关系系统。 由于支持关系模型的程度不同,实际的数据库系统可以分 为表式系统、(最小)关系系统、关系完备的和全关系的四 类系统。 ·查询处理是数据库管理系统的核心而查询优化技术又是 查询处理的关键技术。查询优化一般可分为代数优化和物理 优化。代数优化是指关系代数表达式的优化,物理优化则是 指存取路样和低层操作算法指示变量的选择

设计一个数据库应用系统需要经历六个阶段: 需求分析 概念设计 逻辑结构设计 物理设计 实施 运行维护 设计过程中往往还会有许多反复