I am majoring in inorganic chemistry at university.

Phosphine plays an important role in inorganic chemistry.

He worked hard to accomplish his goals.

This inorganic substance is widely distributed in nature.

His role is the team leader.

Health is very important.

His opinion is very important.

He is majoring in chemistry at university.

He is an expert in chemistry.

He received the letter challenging him to a duel and began preparing for the duel.