He was appointed as the new project leader.

He was alone in the room.

There are a lot of wrigglers in this puddle.

He always speaks honestly about things and is respected by people.

I was chosen as a committee member of the school.

Participation is optional.

He chose to act on his own free will.

He is tackling his job with all his might and sincerity.

I am participating in the committee for the new project.

This problem can be solved easily.