When inserting or removing text, you may end up with an uneven right margin. You can use the FILL command to fill text between the left and right margins (the right margin is defined by the SET WRAP command; see "Setting Autowrap").
Select a block of text to fill as follows:
Place the cursor at one end of the desired range of text.
Press SELECT (SELECT or KP-DOT).
Move the cursor to the other end of the desired range.
Once you have selected the appropriate range, use FILL (PF1,KP-8). This will fill the selected text between the left and right margins.