He is doing special exercises to strengthen his extensor carpi ulnaris.

He is doing special exercises to strengthen his abductor pollicis brevis.

He is doing special exercises to strengthen his abductor pollicis longus.

He underwent surgery on the depressor septi nasi.

I like memorizing the Hyakunin Isshu.

It's difficult to memorize the Hyakunin Isshu.

A positive-semidefinite matrix is one of the important concepts in linear algebra.

He is studying the shape of a tetrahemihexahedron.

This model of the cubohemioctahedron is very beautiful, isn't it?

He was diagnosed with amyotrophic lateral sclerosis.