The aim of this paper is to show relationships between the different formalism for uncertainty in artificial intelligence and its applications. We introduce a model of fuzzy logic programming (FLP). We propose a solution to the problem of discontinuous restricted semantics of annotated logic programs introducing annotated logic programs with left continuous annotation terms (ALPLCA). We show that FLP and ALPLCA have the same expressive power and both háve continuous semantics. We have soundness and completeness results. This enables us to introduce a new relational algebra. Our procedural semantics enables us to estimate the truth values of answers during the computation. Using this, we introduce several search strategies. Consequences of many valued-logic abduction and many-valued resolutions are also discussed.