Constructing Automaton with the Closure of Language Calculation

It is difficult to construct automaton that receives sophisticate language, but we can transit simple languages to complicate languages through calculating between them. Based on the characteristic of right-line language, context free language and context sense language, this text bring up the method of constructing simple automaton to complex automaton. It is easy and utility. It is also can be used of the academic bases for proving the closing in language with FA.