P-F method provides the reusable mechanism of the software process with intuition and accurate. The reusability of software processes is very important feature like the reusability of software products. Three levels of reusable mechanism of P-F method for modeling the software process are the process template, the pattern and the meta pattern. The process template represents the reusable class of process parts described by P-F method. The pattern is the topology structure of the template. The lowest reusable level is meta-pattern, which is basic style of pattern and is also part-style for constructing the well-structured processes/patterns. Using metapatterns, it would avoid the ill structures of software processes and enhance the management of software processes. The operations among the template, pattern and meta-pattern are formally defined, which help to define, reuse and integrage software process. The reusability feature enhances the advantages of P-F method in many aspects: easing the communication among the different management layers; changing demands from recent rapid shift environment; providing the process tolls to creation, analyze, execute, control, commit process responsibility; supplying the convenience of documentation. Because P-F method is quite abstract, it also could be applied to general processes, and implemented by a P-F virtue machine or P-F computing machine driven by the P-F engine. The prototype is undergoing.