1. Food, water, and shelter are considered basic necessities for survival.
食物、水和住所被视为生存的基本必需品。

2. In times of crisis, people often prioritize their needs and focus on the necessities of life.
危机时期，人们经常优先考虑自己的需求，关注生活的必要性。

3. The invention of the internet has transformed from a luxury to a necessity in today's society.
互联网的发明已经从今天的社会奢侈品转变为必需品。