interpreting variables containing in another variable

I've got a variable - $email_body, that contain's other variables. For example, echo "$email_body," might look like this: $name, $address, $phone, $blah I want those variables to interpreted with corresponding values set earlier in the script. So, in effect, where name=bob, address=101 east main, phone=555-5555, and blah=foo, echo "$email_body" would look like this: bob, 101 east main, 555-5555, foo Any suggestions? Thanks in advance. -Bob