Using span within a button control

Hi
Simple enough question I think. Im using a span tag within a button control but I cant seem to enclose it correctly.
<asp:Button ID="Button1" CssClass="showhide" OnClick="return false;" runat="server" <span> class="showhide-text">Show more</span> />
I have tried to add the approbiate closing tags but I cant seem to get it to work for me.
Thanks if you can help.


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