Antonyms are words that have opposite meanings of one another. When it comes to the phrase "not know," some of the antonyms could be "know," "understand," "comprehend," and "be aware of." Other possible opposing words could include "recognize," "realize," and "perceive." Each of these antonyms highlights the concept of gaining knowledge or awareness of something. While "not know" suggests a lack of understanding or ignorance, its antonyms emphasize the importance of becoming familiar with a subject, whether it is feeling confident in one's knowledge or simply acknowledging its existence. Using antonyms helps to provide clarity and enhance understanding by providing a contrasting perspective to a concept.