to sense; to perceive; to become aware of; to detect

to watch; to look carefully at

clean; spotless

to investigate and accept

to make an investigative visit; to go and find out from the source

police; police officer

to observe; to watch; to survey

to supervise; to superintend; inspector; censorship

to investigate a crime; to scout; to reconnoiter; reconnaissance; detection; a scout

to inspect; to observe and study; on-the-spot investigation