He is an expert in osteology.

His role is the team leader.

He goes to the gym every day to train his brachioradialis muscle.

She started strength training for the iliococcygeus muscle.

In Sanskrit phonology, retroflex sounds play an important role.

A back vowel is a sound where the back of the tongue approaches the palate.

Back vowels are vowels that are pronounced using the back of the tongue.

A coronal is a sound that is pronounced using the tip or the upper part of the tongue.

Retroflex sounds are difficult to pronounce.

Retroflex is a phonetic feature that does not exist in Japanese.