He is always acting the maggot and causing trouble.

He is acting the jennet in the play.

This fast-acting medicine will relieve your pain in minutes.

This is the fastest-acting medication I have ever used.

This new medication is faster-acting than the previous one.

This medication is slower-acting than the previous one.

This medicine is the slowest-acting one I've ever taken.

The medication is slow-acting and may take a few weeks to show results.

She is acting upon her instincts.

She is second-acting in the play.