Slipped

The pencil slipped from the desk onto the floor.

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

He slipped the envelope from his grasp and it fell between the seats in the car.

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

The water level slipped as the drought continued.

The key slipped out of the lock and onto the ground.

I slipped up and forgot to send the important email.

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