Now, whenever we're using this formula and we're trying to determine degree bond saturation, we have to follow three important rules. Rule number one, replace all halogens with hydrogens. Rule number two, whenever you're given a molecule or compound with oxygens or sulfur, omit the oxygens and sulfur in your formula. And rule number three, remove nitrogens along with one hydrogen per nitrogen atom. So let's look at how we can use this rule and how we can use or how we can use this formula and these three rules. So let's begin with example one.