His smile was ephemeral, disappearing in an instant.

I'm always impressed by his astonishing talent.

He has a passive personality and rarely takes action on his own.

This project is making substantial progress.

This is the final plan.

I think his ideas are revolutionary.

He reflexively dodged the ball.

His opinion is always rational.

His painting is very realistic, it's just like a photograph.

This reaction occurs through a chemical process.