What's your Weakness?

Pranav got an assignment from school for listing down his strengths and weaknesses. We decided to make it fun and each of us started to state a strength and a weakness for Pranav. For weakness, I began by saying ‘Lack of….’ and paused a second to think of a suitable word. Pranav, without thinking twice, completed the phrase for me, with – ‘MONEY’!! 


After the laughter subsided, we saw he was still perplexed and defended himself by saying .. "of course ! Lack of money is my weakness !" 


How to argue that ?