He always has a golden necklace around his neck.

Humans can make mistakes.

The color of that entrance is mysterious, creating a mystical atmosphere.

I am currently living in Tokyo.

What is the origin of this word?

He is majoring in linguistics.

The atomic number of helium is 2.

An isotope refers to elements with the same atomic number but different numbers of neutrons.

Rare earth elements are essential materials for the manufacture of electronic devices.

Hydrogen is the most abundant element in the universe.