Copying sequences

      <xsl:stylesheet
                  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
                  version="2.0">
            <xsl:output  method="xml"
                        indent="yes"
                        omit-xml-declaration="yes"/>

            <xsl:template  match="/aaa">
                  <xsl:copy-of  select="(bbb,ccc,ddd,bbb)"/>
            </xsl:template>

      </xsl:stylesheet>

      <aaa>
            <bbb>B1</bbb>
            <bbb>B2</bbb>
            <ccc>C1</ccc>
            <ccc>C2</ccc>
            <ccc>C3</ccc>
            <ddd>D1</ddd>
      </aaa>

      <bbb>B1</bbb>
      <bbb>B2</bbb>
      <ccc>C1</ccc>
      <ccc>C2</ccc>
      <ccc>C3</ccc>
      <ddd>D1</ddd>
      <bbb>B1</bbb>
      <bbb>B2</bbb>