Currently completion occurs for system functions and procedures, parameters, reserved words, and user identifiers. Insert the following character literally. When in the insert mode, any non-control character is inserted at the current cursor position. The command mode is then entered by typing the Esc key. In the command mode, various commands are given a range giving the extent to which they are performed.
P Insert the contents of the yank-buffer before the character under the cursor.
Insert the contents of the yank-buffer before the character after the cursor. Pressing Esc returns to the command mode. U u Undo the last change. X Delete the character to the left of the cursor. Delete the character under the cursor.