1. A robot apparatus acting autonomously based on an inner state of the robot apparatus, comprising: storage means for speech recognition, as a dictionary for speech recognition, having stored therein the relationship of correspondence between a word and the pronunciation information thereof; word sound expression storage means, as a table for word sound expressions, having stored therein the relationship of correspondence between the word and the word reading expressing letters thereof; imaging means for photographing an object; image recognition means for extracting the predetermined patterns of images from the image photographed by said imaging means; sound collecting means for acquiring the surrounding sound; speech recognition means for recognizing the speech from the sound collected by said sound collecting means; reading information generating means for conferring plural word reading expressing letters, inferred from the predetermined patterns of images extracted by said image recognition means, based on said table for word sound expressions, and for generating the pronunciation information corresponding to the reading for each of the plural word reading expressing letters or characters thus conferred; and storage controlling means for comparing the pronunciation information generated by said reading information generating means to the pronunciation information of the speech recognized by said speech recognition means and newly storing the closest information of pronunciation in said dictionary for speech recognition as being the pronunciation information corresponding to the pattern recognition result extracted by said image recognition means.