Python 3, 126 bytes

A port of my Jelly answer works well in Python too...

print(*(' '.join([w[2:-1],w[2:],w[:-1],w])for w in"agar abreacts acknowledges codeterminations deindustrializations".split()))

Try it online!

Prints:

a ar aga agar react reacts abreact abreacts knowledge knowledges acknowledge acknowledges determination determinations codetermination codeterminations industrialization industrializations deindustrialization deindustrializations