<!ELEMENT ROOT (A,B) >

<element name="ROOT">
 <complexType content="elementOnly">
  <element ref="t:A">
  <element ref="t:B">
 </complexType>
<element>

<!ELEMENT ROOT (A|B) >

<element name="ROOT">
 <complexType content="elementOnly">
  <choice>
   <element ref="t:A">
   <element ref="t:B">
  </choice>
 </complexType>
<element>

<!ELEMENT ROOT (A|(B,C)) >

<element name="ROOT">
 <complexType content="elementOnly">
  <choice>
   <element ref="t:A">
   <sequence>
    <element ref="t:B">
    <element ref="t:C">
   </sequence>
  </choice>
 </complexType>
<element>

<!ELEMENT ROOT (A?,B+,C*) >

<element name="ROOT">
 <complexType content="elementOnly">
  <element ref="t:A" minOccurs="0">
  <element ref="t:B" maxOccurs="unbounded">
  <element ref="t:C" minOccurs="0" maxOccurs="unbounded">
 </complexType>
<element>

<!ATTLIST ROOT
    a CDATA #REQUIRED>

<element name="ROOT">
 <complexType content="elementOnly">
  <attribute name="a" type="string" use="required"/>
 </complexType>
<element>

<!ATTLIST ROOT
    a CDATA #IMPLIED>

<element name="ROOT">
 <complexType content="elementOnly">
  <attribute name="a" type="string" use="optional"/>
 </complexType>
<element>

<!ATTLIST ROOT
    a (x|y|z) #REQUIRED;>

<element name="ROOT">
 <complexType content="elementOnly">
  <attribute name="a">
   <simpleType base="string">
    <enumeration value="x"/>
    <enumeration value="y"/>
    <enumeration value="z"/>
   </simpleType>
  </attribute>
 </complexType>
<element>

<!ATTLIST ROOT
    a CDATA #FIXED "x">

<element name="ROOT">
 <complexType content="elementOnly">
  <attribute name="a" type="string" use="fixed" value="x"/>
 </complexType>
<element>