Keen

adj.energetic, capableprofessional

Meaning 1

Quick to understand patterns, implications, or small but important differences.

Reach for it when describing sharp perception or analysis

The keen editor noticed that the two promises could not both be true.

everyday
sharp
quick intelligence is being praised informally
not when Sharp may sound abrupt or refer to appearance, pain, or tone.
professional
perceptive
someone understands what details reveal about people or situations
not when Perceptive is about noticing meaning, not necessarily reasoning quickly.
formal
astute
practical intelligence produces shrewd conclusions
not when Astute can imply strategic self-interest where warm praise is intended.
formal
discerning
good taste or careful discrimination separates strong options from weak ones
not when Discerning does not convey the speed or intensity suggested by keen.

Strongly eager to begin or take part.

Reach for it when showing willing interest in an opportunity or activity

Amir was keen to learn every station in the workshop.

playful
game
someone is cheerfully willing to try
not when Game is too casual for a resume or formal recommendation.
everyday
eager
readiness and desire to start are central
not when Eager can suggest impatience when calm commitment matters more.
professional
enthusiastic
visible positive energy will benefit a team or application
not when Enthusiastic does not promise the sustained effort that motivated implies.
professional
motivated
the person is prepared to direct effort toward a goal
not when Motivated focuses on drive, not genuine interest in this particular opportunity.

The definition and the example on this page are written here. The dictionaries above ground which meaning is being described, not the wording.