LOTOS is a formal specification language, designed for the precise description of open distributed systems and protocols. Our purpose is to introduce the operators of logics (for example, disjunction, conjunction, greatest fixpoint, least fixpoint in μ-calculus) into (basic) LOTOS, in order to describe flexible specifications. Disjunction operators ∨ have been already proposed for expressing two or more implementations in a flexible pecification. In this paper, we propose an extended LOTOS with two state operators. They can control recursive behavior, in order to express eventuality. The eventuality is useful for liveness properties that something good must eventually happen. Then, we present a method for checking the consistency of a number of flexible specifications, and a method for producing a conjunction specification of them