Carpeted floor, draped windows and/or walls, acoustical ceiling, and other things that would keep the reverberation down would be helpful.
(other things; would keep down; the reverberation) (Carpeted floor, draped windows and/or walls, acoustical ceiling, and other things; would be; helpful)
other things Carpeted floor, draped windows and/or walls, acoustical ceiling, and other things
would keep down would be
the reverberation
helpful