Use a Vgroup. Inside it place two TextArea components.
Place this inside HGroup alongside a label
<s:HGroup left="10" right="10" top="10" bottom="10">
<s:VGroup left="10" right="10" top="10" bottom="10" gap="0">
<s:TextArea id="row1_text" width="400" height="100"/>
<s:TextArea id="row2_text" width="400" height="100"/>
</s:VGroup>
<s:Label id="myLabel"/>
</s:HGroup>