SKILL

SKILL : (n)

Ability gained through practice ; expertise. (skilled)

LEARN: (N)

The process of acquiring knowledge, understanding or mastery of a study or experience.

Learner(n)-Learnable(adj)-  Learn(v)

KNOW: 

To be familiar with or have experience of.

KNOW-HOW:

 Knowing to do something.

KNOWLEDGE(n):

Having ability to know facts ,information.

KNOWLEDGEABLE(adj):

The state of being intelligent.

KNOW-NOTHING(n):

An extremely stupid person