The goal of this shared task is developing the computer-assisted tools to diagnose several kinds of grammatical errors, i.e., redundant word, missing word, word disorder, and word selection. The input sentence contains one of defined error types. The developed tool should indicate which kind of error type is embedded in the given sentence and its occurred positions. If the input contains no grammatical errors, the tool should return: sid, correct. The output format should be a quadruple of sid, start_off, end_off, error_type , if the input contains a grammatical error. In this output format, sid means the unique sentence identifier, start_off and end_off represent the positions of starting and ending character where a grammatical error occurs, in which each character or punctuation occupies 1 for counting positions, and error_type should be one of defined errors.