you can't judge a book by its cover idiom saying
勿只凭外表判断；不能以貌取人
said to show that you cannot know what something or someone is like by looking only at that person or thing's appearance
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。