AUDACITY HELP!?!?!?!?

i got steps to follow to make a karaoke track on audacity. i did the karaoke track and everything is ok but there is still like an echoing of the girls voice...? how do i get rid of the echo...it sounds like the girls is singing in an auditorium or gymnasium or something like that...??? i also recorded me singing in another track and i put it all together and it just didn't sound right with my voice and the other persons voice in the background...? please answer!!!!!!!