必須

The quality of being convenient or useful for a particular purpose. Often used when discussing urban development, technology, or transportation in IELTS.

To contribute to a result or cause. It is a formal synonym for 'kouken' (contribution), often used when a factor helps bring about a specific outcome.

To put something in good condition or to prepare a system, infrastructure, or legal framework for use. It covers everything from car maintenance to urban planning.

The act of picking between two or more possibilities. It can refer to simple choices or complex strategic decisions.

That cannot be avoided; certain to happen; inevitable.

Multifaceted or many-sided; involving or considering many different aspects or viewpoints.

To occur as a consequence of or in connection with something else; to be incidental or accompanying.

The act of avoiding something unpleasant, dangerous, or difficult. It can refer to physical avoidance or avoiding a specific outcome or responsibility.

Overwhelming or overpowering; having such a great advantage or power that opposition is impossible.

To fall under a certain category, rule, or condition; to correspond to something.