I, being a native English speaker, and having snoozed through some of my grammar lessons in elementary school, sometimes cannot express differences that I feel exist in certain grammatical constructs. Here is such a case:
The car is.
The car is blue.
What is the name for the word "is" when used in the first sentence, and in the second? I feel that these two sentences have different semantic meanings for it, the former being "exists" and the latter not being "exists".
While the second sentence could be rephrased as "The property of blueness exists in the car" I think that that is a completely different way of stating the thought, not an equivalent.
I think the latter is called a "copula" perhaps? No idea for the former.