<sub> (Subscript) Description .email comment.
Description
This element contains a subscript character, word or phrase:
Water is H<sub>2</sub>O.
Water is H2O.
The element complements the <sup> element.
Parent Elements
The elements listed below may directly contain this element. They are "parent" elements. Elements in referenced groups are included, up to two levels of group nesting.
Model Diagram
The DTD model for this element:
--+(choice of TEXT with elements repeated) 
  |  
  |--+(choice) [Formatting in Text]
  |  |  
  |  |-- sub  -- (TEXT and elements)
  |  |  
  |  |-- sup  -- (TEXT and elements)
  |  |  
  |  |-- b  -- (TEXT and elements)
  |  |  
  |  |-- i  -- (TEXT and elements)
  |  |  
  |  |-- smallcaps  -- (TEXT and elements)
  |  |  
  |  |-- u  -- (TEXT and elements)
  |  |  
  |  |-- box  -- (TEXT and elements)
  |  |  
  |  |-- roman  -- (TEXT and elements)
  |  |  
  |  |-- script  -- (TEXT and elements)
  |  |  
  |  |-- tt  -- (TEXT and elements)
  |  |  
  |  |-- strikethrough  -- (TEXT and elements)
  |  |  
  |  |-- overline  -- (TEXT and elements)
  |  |  
  |  |-- newpage  
  |  |  
  |  |-- query  -- TEXT
DTD Definition
The DTD contains the following element and attribute definitions (note that embedded links are to definitions within the DTD page of this guide):
<!ELEMENT sub                            (#PCDATA | %FormattingInText;)*>
<!ATTLIST sub
               %a-group-CommonIDAttrs;>
.
Defined in DTD section Inline-level Content : Formatting and Identifying : Format-Oriented
General Attributes (shared with other elements)
Common Optional ID Attributes (a-group-CommonIDAttrs)