Possible Clues:

• Chortle when sober man gets into a row
• A nervous high-pitched laugh
• Does not drink in the row with a laugh
• One teetotaller in a row? What a giggle!
• A high-pitched nervous laugh
• Laugh nervously in high-pitched way
• Nervous or affected laugh
• One does not drink in a row of giggling
• The teetotaller will laugh a little at being in a row
• Silly little laugh