3. A document processing unit as claimed in claim 2, wherein said layout means obtains a first distance d1 and a second distance d2 by dividing a distance D of an overlapped portion of a first comment and a second comment in a predetermined direction in accordance with the largeness of the first comment and the largeness of the second comment, and moves the positions of the first comment and the second comment by the first distance d1 and the second distance d2.
3. A document processing unit as claimed in claim 2, wherein said layout means obtains a first distance d1 and a second distance d2 by dividing a distance D of an overlapped portion of a first comment and a second comment in a predetermined direction in accordance with the largeness of the first comment and the largeness of the second comment, and moves the positions of the first comment and the second comment by the first distance d1 and the second distance d2. 4. A document processing unit as claimed in claim 3, wherein said layout means checks whether a comment group including a plurality of comments adjacent to each other overlaps with other comment group, and the plurality of comments included in the one comment group are moved if there is an overlap.