"You have to mix everything with cream."
Translation:Du måste blanda allting med grädde.
I'll try to elaborate, but I'm not sure if this helps a whole lot.
So if you must or have to do something, there is some force or circumstance that put you in a situation where you cannot avoid doing something.
If you need to (in the behöver sense) do something, either there is an inner force within you, or it is logically not possible to do action A without first doing action B.
Prototypical cases could be: you must do something because someone who has power over you says so. You need to do something because of something within yourself.
In many real situations there is considerable overlap (you can interpret many situations in different ways), but it would seem that at least in some versions of English, the overlap in usage is much bigger than in Swedish.
Example of something you say in English that does not really make sense in Swedish: You need to shut up – 'behöver' would not make sense here. When you say this phrase, what you mean is that you think I should be quiet. You do not think it's an inner necessity of mine. From a Swedish point of view, the use of need is surprising here, because of what I tried to explain above. As I said, I'm not sure all this helps a lot.
In situations like this, I always forget how similar Swedish is to German: benötigen = behöver = need and müssen = måste = must. When learning Swedish via English I view most phenomena of the Swedish languages like an Englishman and forget how similar it is to my mother tongue. How you put it, it makes perfect sense. Need is something perceived subjectively. E.g. the need to eat. While must is a much stronger word and implies that the necessity is something we can't really influence. Thanks for the input :)
Perhaps one way to think of it is that you can "have a need". If you're hungry, you have a need for food. But you never "have a must", because that's an external interest. It's not something you have, it's something cast onto you.
We do use them largely interchangeably in English, although I think there may be some amount of intention in the subversion: if I tell someone they need to shut up, I am perhaps subtly implying that it would be in their best interest to, lest some ill fortune befall them. i.e. "If you know what's good for you, you will shut up."
If i tell someone "they need to shut up" it would be because its in their best interest to stop talking and not say what they are saying, it is their choice. All im doing is pointing out that its up to them and helping to point out the inner necessity. Im implying that its up to them. So im a bit surprised the subtlety is lost in Swedish. If i tell someone "they have to shut up" its because they shouldn't be talking at all for any reason and they dont get to decide, if they want to talk they have to go elsehwere. I do get the differences in swedish and largely they are the same in english (for me at least) i think subtle differences are lost and its a shame people use them interchangeably since they are not as interchangeable as some think. Definitely helped me to understand the usage better in Swedish.... What would be the best way to say "you need to stop talking" so it implies that what one is saying would be best not said but if you keep talking thats fine because they get to deal with the consquences ?