If statement with Eval function

 <td class="left">  
         <asp:Label ID="lbl" runat="server" Text= '<%# Eval("SomeFlag")%>'></asp:Label>
 </td>
 
How can I redo the Text propery if I want to see other values than True/False that are stored in the database? (for example, instead of having True/False/Null in the list I want to seeYes/No/null.
 
Thanx

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