1) I told him to keep his mouth shut about our secret plan.

2) If you want to avoid trouble, it's best to keep your mouth shut in this situation.

3) She promised to keep her mouth shut about the surprise party.

4) The teacher warned the students to keep their mouths shut during the exam.

5) It's important to keep your mouth shut when you overhear someone else's private conversation.

6) I will only trust you with this information if you can keep your mouth shut.

7) Everyone in the room knew they had to keep their mouths shut to protect the secret.

8) The detective urged the witness to keep their mouth shut until the investigation was complete.

9) If you don't want to be involved in the gossip, just keep your mouth shut.

10) I learned the hard way that it's better to keep my mouth shut than to say something hurtful.