For nearly ten years, the Unified Modeling Language (UML) has been the industrystandard for visualizing, specifying, constructing, and documenting the（ ） of a software-intensive system. As the （ ）standard modeling language, the UML facilitates communication and reduces confusion among project （ ） The recent standardization of UML 2. has further extended the language's scope and viability. Its inherent expressiveness allows users to （ ） everything from enterprise information systems and distributed Web-based applications to real-time embedded systems. The UML is not limited to modeling software. In fact, it is expressive enough to model （ ） systems, such as workflow in the legal system, the structure and behavior of a patien healthcare system, software engineering in aircraft combat systems, and the design of hardware. To understand the UML, you need to form a conceptual model of the language, and this requires learning three major elements: the UML's basic building blocks, the rules that dictate how those building blocks may be put together, and some common mechanisms that apply throughout the UML.
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