I have a question about present perfect

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Sep 15, 2018 01:45
ex: How long have they been married?
They have been married for 20 years.
This is an example of the present perfect in my grammar book. I have a confused about it. The basic present perfect continuous and simple are I have been doing and I have done. There is a ( have been done) in this example. So I was so confused about it.