"Grandmother wants a dog."
Translation:Mormor vill ha en hund.
This isn't actually all that different from archaic English usage - "will" in English is now a modal verb indicating time (having mostly displaced "shall" in that role), but it used to mean "to want", just as in German (and apparently Swedish as well), and would have been used in almost exactly the same manner.
”Ha” means ”have”, ”vill” means ”want”. When you want something, as an object, either abstract or concrete you have to say ”vill ha” (want to have) in Swedish.
- Politikerna vill ha fred. (The politicians want peace.)
- Partiet vill ha en ny lag. (The party wants a new law.)
- Hon vill ha en ny iPad. (She wants a new iPad.)
I'm not a native speaker, but I think if you say "I want to [verb]" instead of wanting to have something then you don't use ha. For example, I want to go is jag vill gå. I don't know of any other exceptions, but if it makes sense to say "have" in English without changing the meaning then it probably needs "ha" in Swedish after the vill.
So is the specification of "ha"/"to have" a grammatical or cultural thing? Like in English, if we want to possess something, we just say "I want [a thing]" but in Swedish, are you just expected to specify a desire to possess, or is "vill" basically meaningless without an infinitive behind it?