In the first stage of learning process knowledge, it is to obtain the statement form of process knowledge, and new knowledge enters the original proposition network and forms a connection with the original knowledge.

In the second stage, after various variant exercises, the declarative knowledge stored in the propositional network is transformed into the procedural knowledge represented and stored by the production system.

In the third stage, the process knowledge is extracted according to the clues to solve the problem of "how to do".