听力原文：There are three kinds of things you need to learn if you want to be able to communicate effectively with Westerners. First, you need to learn a foreign language, usually English. Second, you should learn as much as possible about Western cultures. However, studying English language and Western culture is not enough. You should also learn something about what happens when different people from different cultures try to communicate with each other—in other words, 'intercultural communication.' When you study English, you are not just learning a foreign language. You are learning how to reach across barriers of culture and language. Peace and good relations between nations, people, and cultures need to be based on mutual understanding. As you study English, you are learning how to be an ambassador who can serve as a bridge between China and the world, a 'translator' who can help people of China and other countries better understand each other. The more you understand about intercultural communication, the more effective you will be as an ambassador for your own culture and as a bridge between your culture and others. Question : What is this passage mainly about? (30)