恤衫扣喉鈕一問.

When you go to a formal party, business event, or others formal event, you can 扣頸喉鈕.
People like people 扣頸喉鈕 because they think people 扣頸喉鈕 will look smart and formal.

it is because when you 扣頸喉鈕, it will make you very smart.