1<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" targetNamespace="attr_group_simple" elementFormDefault="qualified"> 2 <xs:include schemaLocation="address.xsd" /> 3 <xs:group name="address2" ref="address1"> 4 <xs:sequence> 5 <xs:element name="road" type="xs:string"/> 6 </xs:sequence> 7 </xs:group> 8 <xs:element name="Student"> 9 <xs:complexType> 10 <xs:group ref="address2"/> 11 </xs:complexType> 12 </xs:element> 13</xs:schema> 14