must与have to辨析

must与have to在英语中均表示“必须”的概念，但在具体使用上有一些微妙的差别。快来看看吧！

must与have to辨析

• 1.must
  • "必须" V情+v原 没有人称和数的变化
  • 出自本人自觉(主观)
  • He must do his homework. 否:He mustn't do his homework. 一般:Must he do his homework？ 肯回:Yes,he must./否回:No,he needn't (doesn't have to)
  • 以must开头的一般疑问句，否定回答时，不用mustn't (禁止，不准)，而用needn't (don't/doesn't have to)(不需要)
  • must本身为情态动词，不与其它情态动词连用
  • 一般疑问句句式:V情+主语十V原+其他？
• 2.have to
  • "必须；不得不" 有人称和数的变化
  • 指外界环境的要求(客观)
  • He has to do his homework. 否:He doesn't have to do his homework. 一般:Does he have to do his homework？ 肯回:Yes,he does./否回:No,he doesn't.
  • have to变各种句式需借助动词(do,does,did)
  • have to可以与其它情态动词连用. 例如:Will he have to tomorrow？
  • 一般疑问句句式:V助+主语+have/has to+其他？