Hallo, input xml is like this

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<?xml version="1.0" encoding="UTF-8"?>
<a>
  <b id="1">
    <c>111 a</c>
    <c>222 a</c>
    <c>333 a</c>
  </b>
  <b id="2">
    <c>111 b</c>
    <c>222 b</c>
    <c>333 b</c>
  </b>
  <b id="3">
    <c>111 c</c>
    <c>222 c</c>
    <c>333 c</c>
  </b>
  <b id="4">
    <c>111 d</c>
    <c>222 d</c>
    <c>333 d</c>
  </b>

</a>

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my xsl is

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  version="1.0">

<xsl:output method="xml" indent="yes" encoding="utf-8"/>

<xsl:template match="a">
  <xsl:copy>
  <xsl:for-each select="node()|@*">
    <xsl:apply-templates select="." />
  </xsl:for-each>
  </xsl:copy>
</xsl:template>

<xsl:template match="b">
  <xsl:copy>

  Hello
  <inside> <xsl:value-of select="c[1]"/> </inside>
  please proceed
  
  </xsl:copy>
</xsl:template>

</xsl:stylesheet>

Thanks in advance