This is the 4363rd most frequent Chinese word.
必需品
Essential item.
必需品 is used to indicate that water is an essential item indispensable for living.
水是人类生活的必需品。
Water is a necessity for human life.
必需品 refers to the necessary documents required for international travel.
在旅行时，护照和签证是必需品。
During travel, a passport and visa are necessities.
必需品 is used to designate items essential for academic activities.