English as a Second Language/Have to and must


Dear Shannon,

Quote from English for starters 9 - Activity Book - by Cheryl Pelteret)

Help box:Use 'have to' to express strong obligation coming from someone else and 'must to' express obligation coming from you. Use should to express mild obligation.

4. Complete the text with should/shouldn't, must/mustn't or have to/don't have to.

When you write a story, you 'must' remember to use the correct punctuation. Remember, in English, you 'must' start a sentence with a capital letter, and you 'mustn't' forget to put a punctuation market at the end of it...


Of course, to me the answers provided in the answer key are confusing and contradictory enough because the author chose one option only, namely 'must', although to me 'have to' is the correct one.

Please help me out.

Lots of thanks.
Kindest regards,
Antoine Ghannoum

You know, in American English, we rarely use "mustn't."  The truth is, there isn't a huge difference between must vs. have to (when used in the positive).  Both are obligations, so don't worry about the extremely slight difference.  The thing to remember is that there is a change in meaning when used in the negative.

You have to clean your room.   = You have an obligation to clean your room.
You don't have to clean your room.  = It is not necessary / it is optional to clean your room.

You must clean your room.  = You have an obligation to clean your room.
You must not clean your room.  = You are forbidden / not allowed to clean your room.

English as a Second Language

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Shannon Cole


I can answer questions related to learning the English and Spanish language.


I have taught ESL and Spanish since 1998 at the university and middle school levels. I am a native of the U.S., and have taught in both the U.S. and Mexico.

I am owner and operator of www.coleinstitute.com, an online language school.

Georgia TESOL in Action (1999)

B.A. in Spanish; M.Ed. in Language Education

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