PURPOSE:To attain the input without noticing the operation between phrases at input, by checking the end of an inputted sentence and providing several space lines with the next phrase when the end is discriminated as the end of each phrase. CONSTITUTION:A sentence end control section 11 discriminates whether the end of sentence comes at each line for the document input from a keyboard 1. When the input key is a code such as end of page or document forming start, the line number is set to an initial value 1. When the input is a carriage return code or the like, the preceding character is searched and it is a period, it is discriminated as the end of sentence, the line number 2 is added. Further, when the horizontal position of a cursor register 4 is equal to the content of a margin register 8 or over, or when the preceding character before the carriage return code is other than a period, the line number 1 is added.