This is the 9823rd most frequent Japanese word.
見せ付け
To show off or flaunt something.
In this sentence, '見せ付けた' is used to emphasize that the act of showing his watch was done in a conspicuous, intentional manner.
彼は自信満々に新しい時計を見せ付けた。
He proudly showed off his new watch.
Here, '見せ付ける' is used to express intentionally displaying talent or skills in a prominent way, often for admiration.
彼女はダンススキルを見せ付けるためにステージに立った。
She stepped onto the stage to showcase her dancing skills.
In this context, '見せ付けています' is used neutrally to indicate the act of presenting or demonstrating.