use 'must or have to'

Hello there, :smiley:

Which of the following sentence is more appropriate from

A/ a farmer’s point of view

  1. I have to take care of the cows.
  2. I must take care of the cows.

B/ a cook’s point of view

  1. It must be difficult to make.
  2. It has to be difficult to make.

Thanks in advance,

mdenglish :smiley:

Usually must expresses somebody’s point of view (what you have in your mind). So,
in A: 1. it’s your duty (arising out of circumstances) 2. is what you think, your opinion.
in B: 1. is more appropriate, it means your supposition bordering on assurance.

You have two different meanings of “must” in your examples.

In A, “have to” and “must” mean exactly the same thing, but “must” is a bit stronger. In both cases, it means the person is obligated to do something. There is no opinion involved.

In B, “It must be difficult to make,” means something like, “It seems to me that this is difficult to make.” There is no obligation involved. The second version, with “have to” means the same thing, but in this meaning “have to” is stronger than “must”.

Not in all varieties. In most varieties “have to” is objective necessity and “must” is subjective necessity, when used as above. Why Americans conflate the two is beyond me.

I think you have this backwards.

“Must” is the term used in laws, rules and other documents that oblige or compel someone to do something. This is OBJECTIVE necessity, as stated by my Collins CoBuild dictionary, among others.

“Have to” is used for both objective and subjective necessity or compulsion.

If you look in ordinary British ESL dictionaries, you’ll see this. There is quite a lot of overlap between the two, but the dictionaries mention laws or rules when defining “must”.

In spoken language there is a difference, because Americans always pronounce the world “must” as [mʌst], whereas the British have a second spoken form that sounds like [mst]. This [mst] form is used to express opinions, so a British person saying, “You [mst] drive by that route,” is really saying, “In my opinion you should drive by that route.”