Start the control limits on the label, found to implement doesn't seem realistic. Should use the textarea control:

<? The XML version="1.0" encoding="utf-8"? >
<S: Application XMLNS: fx="http://ns.adobe.com/mxml/2009"
XMLNS: s="library://ns.adobe.com/flex/spark
" XMLNS: mx="library://ns.adobe.com/flex/mx minWidth"="955" minHeight="600" creationComplete="inital ();" >
<Fx: Script>
<! [CDATA [
import flashx. TextLayout. Conversion. TextConverter.
public function inital () : void {
var STR: String="<the font color='#ff0000 >123456 <the font color=' #32 cd32 >shit </font>";.
TXT textFlow=TextConverter. ImportToFlow (STR, TextConverter. TEXT_FIELD_HTML_FORMAT);
//txtArea text="I am a Chinese I am a Chinese I am a Chinese I am Chinese".
}
]] >
</fx: Script>
<Mx: Canvas x="300" y="300" width="500" height="500" >
<S: TextArea id="TXT" >
</s: TextArea>
</mx: Canvas>
</s: Application>


This concludes the body part