But in the Tips & Notes they give the following explanation:
Fish are tasty = דגים הם טעימים (literally - fish they (are) tasty).
This allows you to differentiate between:
דגים טעימים - tasty fish
דגים הם טעימים - fish are tasty.
Which is why I thought you needed הם in the sentence.
Ok, I looked at adamyoung97's example above: דגים הם טעימים, and it's true, there is a copula and it is an adjective. I guess the difference is דגים is undefinite. If you said דגים טעימים it would be a fragment (unless context), it's just a noun phrase, tasty fish. דגים הם טעימים turns it into a sentence, fish are tasty in general. If the subject is definite however, הדגים, it wouldn't be a fragment because a noun phrase would require the adjective to have a he of definition as well: הדגים הטעימים. So if you say הדגים טעימים it has to be interpreted as a sentence: the fish are tasty. You would also see הדגים הם טעימים with the same meaning, but it's not quite as correct. You would be perectly understood, however. All this must be very confusing. As a native speaker I don't remember ever thinking about these neuances.
It could be confusing, yes. But once you know the nuance, it is very straight forward and I would summarize it like this:
I want a beautiful dog. = אנו רוצֶה כלב יפֶה.
I want the beautiful dog. = אני רוצֶה את הכלב היפֶה.
The beautiful dog is eating. = הכלב היפֶה אוכל.
Dogs are beautiful. = כלבים הם יפים. (here we use the copula because we are generalizing an attribute to ALL dogs)
Not a moderator but a Hebrew speaker.. I would say חם fits both hot warm when translating. חמום has the same meaning as 'hot', in a way, yes, but it's more commonly used to describe a hot tempered person - 'חמום מוח'. Otherwise, it is not so widely used as far as I know (You would not hear anyone say 'הדג חמום' for example. That doesn't sound 'right' at all.)