A binary operator is one of the basic concepts in algebra.

This trumpet is made of brass.

I decided to start a new business taking advantage of this favorable opportunity.

The janitor is cleaning the classroom.

He has a strong sense of public spirit and is always working for the community.

This room is lit only by candlepower.

She was making a fabric using a heddle.

He is a wonderful potter.

I couldn't attend school because of a cold.

Every day, I go to school early in the morning.