必须bìxū 1.表示事理上和情理上的必要;一定要{must; have to; necessary; be obliged to; reasonable and sensible necessity}: 学习~刻苦钻研。{Diligent and intensive study is a fundamental necessity.} 2.加强命令语气{[used to add weight to an order]}: 明天你~来。{You must come here tomorrow.}‖[注意]NOTE: ‘必须’的否定是‘无须’、‘不须’或‘不必’。{The negative of ‘must; have to; necessary’ is ‘not have to; not be necessary; need not’ or ‘unnecessary’.}