He was fearful 'to the extent that' he refused to leave his house. [=he was so fearful that he refused to leave his house]
This new tax affects everyone 'to a greater or lesser extent'. [=it affects some people more than it does other people]
He studied only 'to the extent that' was required to pass the exam. [=he studied just enough to pass the exam]
(..) a commitment they didn't want to make. And now we have this really wonderful facility. It's really a dream come true. This time, we go in with, to some extent ... ... a cult-fan following, which is the greatest type ... ... of encouragement you could have.. There's a lot less anxiety (..)2001 The Matrix Revisited