An English-language 'fragment' L//N//S, which is used for writing program specifications, is defined using the algebraic language ASL/***. In order to define the semantics of L//N//S, the translation from each sentence in L//N//S into a formula in a formal system is defined. If a sentence s in L//N//S is translated into a formula t, then the semantics of s is defined to be the semantics of t in the system. The definition of 'nonlogical' words such as nouns and verbs are given as axioms. A processing system for natural-language specifications that is based on this method has been implemented. Since the number of nonlogical words is very large and their semantics depend on problem domains, it seems to be difficult to define the semantics of all the words from the beginning. The system not only translates specifications into formulas but also supports dictionary expansion. Several specifications have been analyzed using the system, and the nonlogical words have been defined and stored in the dictionary.