Examples of setting vi options temporarily

1. To set the wrapmargin:

   :set wm=5

This sets the wrapmargin to five characters. In insert mode, text will automatically wrap to a new line when the cursor is five characters from the right edge of the screen.

2. To display line numbers:

   :set number

This causes vi to display a line number (starting at 1) at the start of every line of text.