Formatting between marks
If you have two marks, say a and b, then to format the code between the two marks do:
To add arguments such as column width do the following:
Formatting by paragraph
Vim delineates paragraphs based upon empty lines e.g.
This is paragraph number one. This is paragraph number two. Notice the space between them.
To auto format a paragraph place the cursor on a line in the paragraph and type the following: