问如何在蜂箱中使用多个子查询

EN

SELECT
cfs.roll_no,
max(cclas.crdm_cd) as crdm_cd,
max(cclas.kjtm_cd) as kjtm_cd
FROM cust_focus cfs
LEFT JOIN cust_class cclas
ON (cfs.CF_CLAS_NO = cclas.CLAS_NO
AND cfs.DFS_CD = cclas.DFS_CD 
AND cclas.D_AREA = 'US' 
AND cclas.active_flag = 'Y')
WHERE cfs.roll_no NOT IN (SELECT roll_no FROM class_hist)
AND UPPER(TRIM(cfs.D_AREA)) = 'US'
AND (cfs.master_cd IN (SELECT msk5.msk5_master_cd from msk5_mst_tbl as msk5 WHERE cfs.master_cd=msk5.msk5_master_cd and msk5_m_code=9)
OR cfs.master_cd IS NULL)
group by cfs.roll_no;