Slipped

The spy slipped the secret code into the message, without anyone realizing it.

The secret plan was slipped into a confidential memo, without anyone noticing.

He slipped on the wet pavement and sprained his ankle.

The papers slipped out of the folder and scattered across the desk.

He slipped on the banana peel and landed on his backside.

She slipped on the icy sidewalk and slid several feet before coming to a stop.

The traffic slipped away as she drove out of the city.

The piece of paper slipped from the bulletin board and fluttered to the ground.

The spy slipped past the guard and entered the building undetected.