* "The keenness of her gaze revealed her intense focus on the task at hand." (This emphasizes the intensity of her focus)
* "The keenness of his mind was evident in his insightful analysis of the situation." (This highlights his intelligence and sharpness of thought)
* "Despite the cold, the hikers continued their journey with unwavering keenness." (This shows their strong determination and enthusiasm)
* "The keenness of his senses allowed him to detect the faintest sounds in the forest." (This emphasizes his heightened awareness and sensitivity)
* "The keenness of her ambition drove her to achieve great things." (This highlights her strong desire and drive)
These are just a few examples. The best way to use "keenness" in a sentence depends on the specific context and what you want to emphasize.