Question

define reverberation and suggest two ways to reduce it

Answer 1

Reverberation or reverb is created when the sound is reflected off different surfaces in its range. These reflections build up and eventually die out due to absorption by the different objects/surfaces.
Reverberation can be reduced by replacing the hard surfaces with soft ones or covering them. You can place carpets on the floor or use heavy pleated drapes that absorb sound wonderfully.

Answer 2

Reverberation is a persistence of sound after the sound is produced.

reverberation can be reduced by keeping hard walls rather than soft ones..