The concept of antonyms or opposite words is integral to the English language. In the case of the phrase 'wert convinced', some of the antonyms that come to mind include 'doubtful', 'uncertain', 'wavering', 'unsure', 'hesitant', 'indecisive', 'unconvinced', 'skeptical', 'disbelieving' and 'distrustful'. These words describe an individual who lacks trust or certainty in a certain situation, idea or person. Antonyms are essential in communication, as they help provide clarity and more detailed expression of a concept. They can also help individuals expand their vocabulary and become more proficient in the use of the English language.