<xsl:choose>
<xsl:when test="foaf:PersonalProfileDocument/dc:title">
<xsl:value-of select="foaf:PersonalProfileDocument/dc:title"/>
</xsl:when>
<xsl:otherwise>
<xsl:attribute name="xml:lang">
<xsl:text>en</xsl:text>
</xsl:attribute>
<xsl:text>FOAF</xsl:text>
</xsl:otherwise>
</xsl:choose>
en
FOAF
and I know ...