The Scottish composer Evelyn Glennie lost nearly all her hearing as a young girl, yet went on to a very successful career in music including winning Grammy awards. When somebody asks her, "How do you hear"? She responds, "How do you hear? Is it only with your ears?" For Glennie, and for us too, listening is not only hearing, but is understanding. We need to listen to what is said and unsaid, and also how it is said.
It's important to hear what people say accurately. As Mark Twain said, "The difference between the right word and the almost right word is the difference between lightning and the lightning bug(萤火虫)." If you miss something or you're not sure whether you've heard accurately, ask the speakers. At this point you're not evaluating what they say, but just looking for accuracy and understanding. Here are some ways to get clear about what they say and don't say. Why are they saying this now, instead of sooner or later? Why are they emphasising these points, instead of something else?
Listen to how it is said. People send signals about what they mean with their voices and body language that sometimes differ from the words they say. While going through the next points, think about someone whose real meaning you might sometimes miss, and see if any of these signals might come up. First, voices. When others speak, notice changes in their volume, pace, and tone. Second, body language. Notice gestures, eye contact, and facial expressions. Do these sync what they are saying, or do they tell a different story? Third, emotions. What is the person apparently feeling? Now you might not know for sure, but be considerate, open to understanding, and ask thoughtful questions.