원동력

The occurrence of an event by chance without an apparent cause, plan, or intention.

A higher rank, position, or category in a hierarchy or list.

A lower rank, position, or category in a hierarchy or list.

By chance, accidentally, or unexpectedly. Often used in TOEFL listening narratives or history passages about accidental discoveries.

Practical use or utility; the quality of being useful in real-life situations rather than just being theoretical.

Successful in producing a desired or intended result; effective.

An act of trying to do something, especially something new or difficult.

Working hard and carefully; diligent. It describes a person who consistently puts in effort and is dedicated to their work or studies.

To be enough or adequate in amount, quality, or degree for a particular purpose.

Including all or nearly all elements or aspects of something; wide-ranging or comprehensive.