XSLT - Applying multiple templates to the same element - xslt

Question

Right now I'm using a replace template which converts <p></p> tags in a new line:
<xsl:template name="string-replace">
<xsl:param name="text" />
<xsl:param name="replace" />
<xsl:param name="by" />
<xsl:choose>
<xsl:when test="$text = '' or $replace = ''or not($replace)" >
<!-- Prevent this routine from hanging -->
<xsl:value-of select="$text" />
</xsl:when>
<xsl:when test="contains($text, $replace)">
<xsl:value-of select="substring-before($text,$replace)" />
<xsl:value-of select="$by" />
<xsl:call-template name="string-replace">
<xsl:with-param name="text" select="substring-after($text,$replace)" />
<xsl:with-param name="replace" select="$replace" />
<xsl:with-param name="by" select="$by" />
</xsl:call-template>
</xsl:when>
<xsl:otherwise>
<xsl:value-of select="$text" />
</xsl:otherwise>
</xsl:choose>
</xsl:template>
I use it like this:
<xsl:variable name="replaceString">
<xsl:call-template name="string-replace">
<xsl:with-param name="text" select="$data/description/text" />
<xsl:with-param name="replace" select="'<p></p>'" />
<xsl:with-param name="by" select="'
'" />
</xsl:call-template>
</xsl:variable>
The thing is that the client now requested that other HTML tags should be interpreted correctly. For example, I want to replace <br>, or to set the font to bold when I have something like <b>Hello</b> inside the text.
For the <br> replacement I wrote this snippet:
<xsl:template match="br">
<fo:block></fo:block>
</xsl:template>
And for the <b> replacement this one:
<xsl:template match="b">
<fo:inline font-weight="bold">
<xsl:apply-templates select="*|text()"/>
</fo:inline>
</xsl:template>
How can I apply multiple transformations to the same text?
A text sample might look like this: Lorem ipsum dolor sit amet, consectetur adipiscing elit. Fusce nisl neque, lobortis ac consequat eu, feugiat a erat. Morbi eget augue dolor. Pellentesque vel laoreet ex. <p></p>Quisque convallis nisl tellus, in rhoncus libero porttitor in. Cras nunc diam, condimentum in ornare ut, mattis in arcu. Nulla ultrices sapien ligula, vel volutpat risus pharetra sed. <br></b>Nunc quis arcu eu ex <b>cursus pellentesque</b> at eget augue.. So it's a string with markup, not an XML with p or b elements.