He was running while holding a bag.

He always carries an umbrella around.

He is majoring in chemistry at university.

Understanding the structure of atoms is a fundamental part of physics.

He is an expert in chemistry.

I commute to work every day on the circle route.

Please cut this apple into four pieces.

He emphasized the importance of the four freedoms.

Understanding data structures is important for improving programming skills.

This building is structurally very strong.