What is a synonym for keen?

The best synonym for "keen" depends on the context. Here are some options:

For enthusiasm/interest:

* Eager

* Ardent

* Avid

* Passionate

* Enthusiastic

* Excited

* Rapt

For sharpness/intellect:

* Sharp

* Intelligent

* Astute

* Perceptive

* Insightful

* Bright

For intensity/force:

* Strong

* Intense

* Vigorous

* Powerful

* Fierce

For sensitivity/perception:

* Sensitive

* Aware

* Observant

* Attentive

* Alert

To choose the best synonym, consider the specific meaning of "keen" in your sentence.