1·The abstract system that an author constructs exists only in his mind, and the physical manifestation — the book — is only a convenient means of storage and distribution.
作者建造的抽象系统仅仅存在于他的脑海里，它的物理表现(书)仅仅是为了方便的保存和发行的一种手段。
2·One that contrives, devises, or constructs something.
发明，设计，或建造某物的人。
3·Although it is easy to define the basic constructs of the ER model, it is not an easy task to distinguish their roles in building the data model. What makes an object an entity or attribute?
虽然建造基本的ER模型是很容易的，但是区别他们在建设数据库时所处的地位并不容易，什么决定了一个对象是实体还是属性呢？
4·China is the world's only country that constructs three 3g communication networks simultaneously.
中国是世界上独一无二的同时建造三套3g通讯网络的国家。
5·Is good while has the people who part of brains do not give off heat to realize in fast constructs the tombstone to the humanity for oneself.
好在有部分头脑不发热的人们认识到人类同时在快速地为自己建造墓碑。