How to pass variable to wget ?

["J. Bakshi" <bakshi12@gmail.com>]

Dear list,


I have a script which submits a form with wget --post-data

[....]

#!/bin/bash

Uname=xyz
Pword=1234

wget -O - --save-cookies cookies.txt --post-data \
'username=$Uname&password=$Pword'  --keep-session-cookies $URL/$AUTHURL   1&>2

[....]

During the test with "bash -x" I see the variables are not evaluated and they appear as
$Uname and $Pword. But if I put an echo for testing at top like

echo $Uname

the value is evaluated correctly.
Am I missing something ? Even the command substitution does not work inside 
wget -O - ...............

Thanks