区别辨析have to与must

have to与must这两个动词均有“必须、不得不”之意。

have to : 通俗用语,指受客观条件或环境迫使而“不得不”做某事,突出客观性。

  • I have to go to San Francisco tomorrow on business.
    我明天得去旧金山出差。
  • What time do you have to be there?
    你得几点钟到那儿?
  • Do we have to finish this today?
    我们今天必须把这事做完吗?
  • We'll have to start keeping detailed records.
    我们不得不开始作详尽的记录。
  • Jackie's ill so they've had to change their plans.
    杰基病了,因此他们不得不改变计划。

must : 通常表示命令或说话人主观认为必须要做某事,含强调语气,侧重主观性。

  • Meat must be cooked thoroughly.
    肉必须完全煮熟。
  • I must get some sleep.
    我必须睡会儿觉了。
  • You mustn't show this letter to anyone else.
    你不许把这封信给其他人看。
  • Luggage must not be left unattended (= it is against the rules).
    行李不能无人看管。
  • Must you leave so soon?
    你非得走这么早吗?
  • "Must I sign this?" "Yes, you must."
    “我必须在这上面签字吗?”“是的,必须。”