这个问题我也问过，我问的还比你多两个：know about ，learn about，我采纳的那个解释是 learn :v. 学习,获悉,记住 了解 1. I'm trying to learn English. 我正在尽力学英语。 2. I learned this news from the newspaper. learn about: vt. 了解(知道) 1. I want to learn about your new policy on investment. 我想了解一下你们的新投资政策。 known :a. 已知的,有名的 vbl. 知道 [计算机] 已知的 1. After chemical assay, we have known the composition of the ore. 经过分析，我们知道了矿石的构成。 2. Your theory doesn't square with the known facts. 你的说法跟已知的事实不符. known about:v. 知道关于...的情况 1. Henry thinks nothing is known about him, but I am told that the authorities have him taped. 亨利以为谁也不知道他的情况，但我听说当局已摸清了他的底细了。 2. She had known about the scheme for some time, but only opted in at the last minute.