He is the main organizer of this event.

He is a very excellent technician.

He is a world-renowned researcher.

The operator is operating the machine.

He is already an adult, so he can make his own decisions.

He is a very talented arranger.

He is a famous lyricist.

He is an expert in computer science.

We need to choose a candidate for the new president.

Who is the producer of this movie?