Slipped

The book slipped from his lap and onto the floor.

The pencil slipped from the desk onto the floor.

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

He slipped and used a curse word in front of his grandmother.

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

The bag slipped off her shoulder and spilled its contents onto the sidewalk.

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