The phrase "明白" means "to understand" or "to comprehend" in English. The word "明白" comes from the Chinese characters "明" and "白," which mean "bright" and "white," respectively. In English, the phrase "to understand" is used to express the idea of having a clear and complete comprehension of something. For example, you might say "I understand what you're saying" to indicate that you have a clear understanding of the speaker's words. In Chinese, you could say "我明白你的意思" to express the same idea.