Because the marriage-skills programs are so new, there is no research on whether they actually prevent divorce.

This is a feature which was implemented with no thought at all to actually preventing its exploit.

Well I can't see that that would actually prevent action.

But the estate tax actually prevents small farms from growing.

Duct cleaning has never been shown to actually prevent health problems.

Yes, it's true - you can actually prevent pregnancy and avoid abortion.

Workers have to clean them and I am not sure there is any evidence to show that such areas actually prevent smoke escaping.

"I think the stone actually prevented the car from coming through into my office area."

This is partly proven by the way they keep trying to pass laws against things that no law can actually prevent.

But there are some things your doctor may recommend that can actually prevent certain cancers in the first place.