For the calculation in the natural language on line, it is necessary to introduce several formulas as follows:  σ 1) W2(σ 2) …Wk(σ k) We now describe an example to illustrate the application of Theorem 1. δ is defined as follows:  In this paper, we have considered some basic probabilistic models of computation by inputting strings of words, and some new conclusions have been discovered.
a major issue to decide upon is how to represent the BNF syntax as a data structure.