How to stifle a yawn in public

• Purse your lips together and almost smile into it. This stops your mouth from flipping open.
• Another option is to throw caution to the wind and yawn, covering your mouth with your right wrist or hand.
• Onother yawn covering materials include fans, handkerchiefs, gloves, menus and books. Dropping  something on the floor at said moment is another handy tip.

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