CSS3 Pseudo-elements

In the CSS3 Selectors module there is the following text:

   7.4 The ::before and ::after pseudo-elements

   When the ::first-letter and ::first-line pseudo-elements are
 combined with ::before and ::after, they apply to the first letter or
 line of the element including the inserted text.

This seems inconsistent with the description of simple selectors:

   4. Selector syntax

   One pseudo-element may be appended to the last sequence of simple
   selectors.

So can multiple pseudo-elements be used in a single selector or not?

Michael