Through discussing how the Polite Principle rescues the Cooperative Principle in English and Chinese ,this thesis proves that PP is suitable both in English and Chinese .What's more, Chinese people has the thoughts and tradition of polite-hess. However when Chinese people confront with English they are easy to fall into embarrassments. Tiffs thesis points out two reasons of pragmatic failure. One is the cultural difference and the different use of PP in Chinese and English. The other is the unsuitable education system and belief. Finally, this thesis proposes three kinds of methods: 1. The supplement of au-thentic material which can reduce inauthentic input, improve cultural awareness and stimulate learning motivation.2.Changing the classroom from the teachers' arenas to students' forums 3. Learning English on the internet.