need Echo help

Hello everyone I am new to editing and I have what I believe is to be a simple question:
How do I echo just a small 2 count section marked off in a song?

I am trying to delete a bad word in a song so what I have done is muted the bad word which is about 2 counts, then what I would like to do is echo another word for 2 seconds to go over the muted section of the song.
The trouble I am having is finding how to echo effect only the word and not the entire song.

Does that make sense? I aporeciate any help

Al