know what you are doing idiom
掌握有效做某事的技能（或知识）
to have the skills and knowledge to do something effectively
You don't need to tell me - I know what I'm doing! 你不用告诉我——我能应付得了！
江苏热线英汉汉英双解词典包含207361条英汉翻译词条，涵盖了常用英语单词及词组短语的翻译及用法，是英语学习的必备工具。