Possible Clues:

• Get rigid
• Stiffen in fear
• Tighten
• Stiffen
• Ill at ease at a wake? You won't relax if you do that!
• Ill at ease at a wake? It will make one's blood run cold!
• Become anxious
• React to stage fright, maybe
• A number drink audibly and become edgy
• Show nerves, in a way