* qa-system ** query-process segmentation: at first segment the query into words. query-analysis: find what kind of query it asks via RULES. lexical-answer-type: find the key word of the query, i.e. what does it want. query-reformulation: ** data-process data-parse: extract the text or table from the raw-data. information-extraction: extract the effictive information from text. ** answer-retrivel: data-retrivel: given a query, return a list of related words/sentence. text inference: no deep learning yet. candidata-answer-rank: rank the answers.