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Is there any difference between these sentences:

  • You must try it.

  • You should try it.

With some respect, I mean when talking to elders.

marked as duplicate by tchrist, choster, Mitch, Dan Bron, Matt Gutting Dec 2 '14 at 17:11

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  • The simple answer is that "must" is a command, and "should" is a suggestion. However, the complete answer is more complicated than that. Can you provide any more context for your question? – Nick2253 Dec 2 '14 at 15:58
  • 1
    Yes, there are differences. But they depend on the politeness system in use, and the relationships of the speaker and the addressee. From a son to a father, from an employee to an employer, from a niece to an aunt -- even specifying elder addressees, there are too many different meanings. – John Lawler Dec 2 '14 at 15:58
  • @Nick2253 thanks, this Should be the answer rather than comment, so that I Must accept it :) – Burgeoning Islam Dec 2 '14 at 16:06

Well, in general, 'must' carries more strength and obligation than 'should'. When speaking to elders, or to persons in authority, 'should' is more polite.

If you are speaking to an elder with whom you are familiar and usually speak with casually, 'must' is okay, but tone of voice is important. It's difficult to illustrate via text, but your tone should sound more imploring and excited than commanding or insistent.

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