By inducing a fact in content security fields that there are Chinese Keywords maliciously jammed with the method of active jamming in Chinese

the concept of active jamming in Chinese is introduced and its formalized description is presented.According to the pattern recognition theory

a flexible pattern matching algorithm in Chinese keywords is presented

based on which the matching of Chinese keywords jammed maliciously with symbols is completed

and the complexity of our algorithm is computed.The technology can avoid classical algorithms of pattern matching in Chinese strings effectively

so that the filtering and intrusion detecting systems included in such algorithms cease to be effective.It is the flexible pattern matching algorithms that can solve the problem of maliciously jamming with active jamming in Chinese string and protect the webs jammed with active jamming effectively.