In mathematics, equivalence classes are a very important concept.

We belong to the same class.

This statue is made of copper.

He found an old copper coin.

This material is a nonconductor and does not conduct electricity.

The iteration mark 々 is used in this kanji.

We studied in a mobile classroom.

The path leading to the shrine is very quiet and beautiful.

Our team was fully mobilized to make the project a success.

His identification was undoubtedly accurate.