To pinpoint exactly the most sensitive or painful aspect of someone or a situation, often revealing a deep-seated issue or vulnerability.

To kill two birds with one stone: solving two problems or achieving two goals with a single action. It is the art of efficiency taken to its maximum expression, and the person who pulls it off always feels like a strategic genius.

To be an adult, have experience and knowledge gained from years lived. Someone who has gray hair knows what they're doing.

To be completely unaffected by something, to be completely indifferent. Someone who is not moved by anything is not bothered by anything.