PURPOSE: To improve the accuracy of a translating by detecting an incorrect or unappropriate part being unsuitable for a translation from in a text, presenting this part and a hint for correcting the text to a user, and supporting rewriting in an easily translatable text.

CONSTITUTION: A text input means 11 inputs a text. A dictionary 12 stores information of a translated word and a part of speech, etc., required for a translation at each head word of original language. A translating means 13 translates the text by referring to the dictionary 12. A difficult sentence deciding means 14 detects the part whose translation is difficult in the text from a result of analysis in a translation process of the text, and generates together advice information for correcting the text. A difficult sentence correcting means 15 presents those parts whose translation is difficult and the advice information, allows a user to execute a correction of the text, and also, delivers the result of correction of the text to the translating means 13, and allows it to execute a translation again. A translated sentence output means 17 outputs a generated translated sentence.