Abstract: The query requirements of large-scale Chinese corpora are different from those of general text retrieval system.Cici v2.0 is a Chinese corpus search system and provides linguistic query services:part-of-speech search,reduplicated words search,wildcard search,and Chinese N-gram string occurrence search.The N-gram string occurrences are accounted and indexed by Unicode and frequency respectively.The search procedure is divided into three steps.First,the Chinese N-gram occurrence statistic records are searched and the candidate n-gram strings are produced.Then,keywords are searched according to user’s linguistic need；At last,these Chinese strings are searched selected by users in the corpora and the final results are returned.

Key words: Chinese character,Corpus,Information retrieval,Part-of-speech,N-gram