Europium is one of the rare earth elements.

I like to take a walk in the park in the early evening.

This email contains ghost characters.

My friend is a doctor.

He is a famous writer.

A proper noun is a noun that refers to a specific person, place, or thing.

Watching the setting sun sink into the sea, I felt at peace.

I mailed a letter at the post office.

Nuclear fusion is expected to be a future energy source.

Organic solvents play an important role in chemical reactions.