Increasing sections of silence in a track

I am using Audacity 2.1.3 in Windows 7.

I have a language learning CD which has pauses for repetition but the pauses are not long enough for a normal person to repeat what was just said for language learning / practice.

Does Audacity have any feature that allows one to increase automatically any period of silence by a fixed amount in a track?
Say increase a silence of 2 seconds to maybe 6 or 8 seconds.

Thank you.

There’s a plug-in here that may help:
For installation instructions, see:

Thank you - looks exactly what I was looking for.