Normal abilities are the things anyone can do with a little training.
Even if you don’t have an Ability to do an action, you don’t lack the ability entirely. You can always use base Statistics like a default. While the ability often grants special advantages.
An example is that anyone can use their AGILITY to reduce fall damage, but only people with the ACROBATICS ability have a passive fall reduction at all times.
Some examples of actions performed by just your base statistics are;
Intelligence for Navigation
Intelligence for Haggling
Strength or Durability for Climbing
Agility for Pick Pocketing
Combat, Melee(Martial Arts)
Hunting & Tracking
General actions also have a variety of generic Advantages and Disadvantages that can modify the function of the action. Things like “Cannot be improved.” or Extra Ability/Bonus modifier. However, since we are not really dealing with vast super powers in this setting the list is pretty small. Advantages and Disadvantages alter the Cost level of an action. These also work very well for crafting Gear.