Class assignment for www.w3.org validation

definiton of span: Applies style information to the content within a document on an arbitrary basis. This element is used where small amounts of text are to receive special style rule treatment. It is used for text only.

Definition of blockquote:
Specifies large chunks of material quoted from external sources, publications, or other materials. This element narrows the right and left margins of the enclosed text to differentiate it from the rest of the document.