PURPOSE: To decrease processing time by providing a flag part retrieval queue part and a retrieval result storing buffer, and executing independently processes each other between a KANA (Japanese syllabary)/KANJI (Chinese character) converting part and an independent word retrieving part.

CONSTITUTION: A KANA/KANJI converting part 4 converts the KANA code string of an input buffer 2 into a KANJI/KANA string. A retrieval queue part 5 stores the information on independent word retrieval starting position which is retreived at a cue retrieving part 3. Then the information is read out of a matrix part 5 as well as an external memory 8 storing the reading information on the independnet words, the information on the parts of speech, etc. to retrieve the independent words through an independent word retrieving part 7. The retrieving result of independent words is stored in a retrieval result storing buffer 6. A flag part indicates the occupied states of the part 5 and the buffer 6 and displays the result of the part 4 at a display part 9. Thus it is possible to perform the KANA/KANJI conversion and the retrieval of independent words at a time.