SELECT 
    LINE_ID AS LINE,
    SEAT_NO AS SEAT_F,
    SEAT_NO + 2 AS SEAT_T
FROM 
    SEAT_RESERVE AS S1
WHERE 
    RSV_STATUS = '0'
    AND EXISTS (
        SELECT 1 
        FROM SEAT_RESERVE AS S2
        WHERE 
            S2.LINE_ID = S1.LINE_ID
            AND S2.SEAT_NO = S1.SEAT_NO + 1
            AND S2.RSV_STATUS = '0'
    )
    AND EXISTS (
        SELECT 1 
        FROM SEAT_RESERVE AS S3
        WHERE 
            S3.LINE_ID = S1.LINE_ID
            AND S3.SEAT_NO = S1.SEAT_NO + 2
            AND S3.RSV_STATUS = '0'
    )
ORDER BY 
    LINE_ID DESC, 
    SEAT_NO ASC;