You must drive carefully.
You cannot run. You must not run.
You can drive at 30kph.
You must stop.
You must wash your hands.
You must wear a hard hat.
You must be silent. You cannot talk.
You can't smoke. You mustn't smoke
You cannot eat or drink. You must not eat or drink.
You must not enter. You cannot enter.
You cannot use your phone. You must not use your phone.
You cannot walk. You must not walk.