PURPOSE: To give no poor result of conversion to a user when the conversion has an internal failure by deciding a section proper as a paragraph as a due paragraph to a series of KANA (Japanese syllabary) strings existing before and after the position where the analysis failed.
CONSTITUTION: A keyboard 14 is provided together with a CPU 15, a CRT display 16, a ROM 17, and a RAM 18. In such a constitution, the range of a paragraph is estimated and at the same time the words composing the paragraph are estimated when the KANA/KANJI (Chinese character) conversion fails. Then the paragraph which is generated and adopted is automatically stored. Thus it is prevented to produce the poor result of conversion and to clear away the unpleasant feeling of a user.