不可或缺

The state of being absent from a place or event where one is expected to be, such as a class, meeting, or ceremony.

To look up information in books, documents, or databases for research or clarification purposes.

To evaluate or assess someone's performance, skills, or knowledge, often as part of a formal system in school or work.

To provide financial aid or support to someone (like a student) or a project.

To analyze and explain something in detail, often by breaking it down into its component parts. It is commonly used for explaining complex texts, data, or technical problems.

To move something or someone from one place, person, or state to another.

To take something as true or as a fact without proof; to suppose or hypothesize.

To keep or continue to have something; to not lose, get rid of, or change something.

To point out; to indicate; to state clearly.

A difficult problem or task that requires significant effort and intelligence to solve.