the penny drops idiom UK informal
恍然大悟，豁然开朗
If the penny drops, you suddenly understand something.
She looked confused for a moment, then suddenly the penny dropped. 她一开始看起来有些不解，后来恍然大悟。
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。