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
Abstract: : based on years of work experience, the author describes the concrete application in highway bridge construction problems, and puts forward some Suggestions.
摘要：作者根据多年的工作经验，讲述了在公路桥梁施工中混凝土技术的应用理由，并提出了一些倡议。
3
The abstract should be within a length of 300 words in English or Chinese. Besides abstract the author should designate which subject the paper belongs to.