If you scored 90% on an Engpsh test, you can say that you did very well or that you did an excellent job. You could also say that you performed exceptionally or that you demonstrated a high level of proficiency in the language. You could also mention specific strengths that contributed to your performance, such as your abipty to understand and use grammar correctly, your vocabulary, or your abipty to read and understand complex texts. Overall, a score of 90% is a very good result, and you should be proud of your achievement.