Where stresses don't naturally exist, the researchers cause them.

Additionally, by definition anything that exists naturally is not supernatural.

Since hydrogen doesn't exist on earth naturally as a gas, we must extract it from other elements.

"Jacob, humans have already produced conditions that never existed naturally anywhere before."

It does not exist naturally, but can be made from the decay of Sr.

This principle insists that such places will not exist naturally in a modern urban fabric.

Definition Caffeine is a substance that exists naturally in certain plants.

Water is the only substance on earth that exists naturally in three states.

However, hydrogen does not naturally exist on Earth in its elemental form.

Sometimes species of bacteria that do not naturally exist in an area will be added to the native population.