1. A speech recognition method, comprising: acquiring a text file and extracting a command word from the text file according to a predetermined rule, to obtain a command word list; generating a corresponding new pronunciation dictionary according to a new command word and performing training to obtain a new language model, wherein the new command word is a command word that is comprised in the command word list but not comprised in a command word library; merging the new language model into a language model library corresponding to the command word library; receiving speech and performing speech recognition on the speech according to an acoustic model, a phonation dictionary, and the merged language model library; obtaining a speech recognition result by means of the speech recognition; determining whether the speech recognition result is a preset flag command word; and if the speech recognition result is a preset flag command word, acquiring a text file corresponding to the preset flag command word.